U.S. patent application number 13/473286 was filed with the patent office on 2012-09-06 for microscope.
This patent application is currently assigned to Olympus Corporation. Invention is credited to Atsuhiro TSUCHIYA.
Application Number | 20120224257 13/473286 |
Document ID | / |
Family ID | 40548478 |
Filed Date | 2012-09-06 |
United States Patent
Application |
20120224257 |
Kind Code |
A1 |
TSUCHIYA; Atsuhiro |
September 6, 2012 |
MICROSCOPE
Abstract
A microscope includes a condenser lens that is provided in an
illumination light path and in which at least one optical device is
insertable into and removable from an illumination light axis for
switching an observation method. The microscope also includes a
first polarizing plate that is provided in a same light axis as the
optical device and is insertable into and removable from the
illumination light axis integrally with the optical device, and a
second polarizing plate that is provided in the illumination light
axis independently from insertion and removal of the optical device
into and from the illumination light axis.
Inventors: |
TSUCHIYA; Atsuhiro; (Tokyo,
JP) |
Assignee: |
Olympus Corporation
Tokyo
JP
|
Family ID: |
40548478 |
Appl. No.: |
13/473286 |
Filed: |
May 16, 2012 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
12350368 |
Jan 8, 2009 |
8203783 |
|
|
13473286 |
|
|
|
|
Current U.S.
Class: |
359/371 ;
359/386 |
Current CPC
Class: |
G02B 21/0088 20130101;
G02B 21/14 20130101; G02B 21/086 20130101; G02B 21/0092
20130101 |
Class at
Publication: |
359/371 ;
359/386 |
International
Class: |
G02B 21/06 20060101
G02B021/06 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 8, 2008 |
JP |
2008-001674 |
Claims
1. A microscope comprising: a condenser lens that is provided in an
illumination light path and in which at least one optical device is
insertable into and removable from an illumination light axis for
switching an observation method; and a polarizer which is provided
in the illumination light axis independently from insertion and
removal of the optical device into and from the illumination light
axis, wherein the polarizer is operable as both of a first
polarizing plate and a second polarizing plate, stores a position
in a first vibration direction for the first polarizing plate and a
position in a second vibration direction for the second polarizing
plate, and can selectively reproduce and hold the stored positions
in the first and second vibration directions.
2. The microscope according to claim 1, further comprising a motor
from which a rotational angle can be detected for selectively
reproducing and holding the stored positions in the first and
second vibration directions of the first and second polarizing
plates.
3. The microscope according to claim 1, wherein: the optical device
is a slit for relief contrast with a third polarizing plate
provided on a part thereof; the first polarizing plate is a
polarizing plate for relief contrast; and the second polarizing
plate is a polarizing plate for differential interference or a
polarizing plate for polarization observation.
4. The microscope according to claim 3, further comprising a fourth
polarizing plate for differential interference or polarization
observation fixedly provided in an observation light axis and
having substantially a same vibration direction as a vibration
direction of the first polarizing plate.
5. The microscope according to claim 3, further comprising a fourth
polarizing plate for differential interference or polarization
observation fixedly provided in an observation light axis, wherein
a vibration direction of the fourth polarizing plate makes
substantially a crossed Nicol condition with the second vibration
direction.
6. The microscope according to claim 3, further comprising a fourth
polarizing plate for differential interference or polarization
observation and a prism for differential interference, wherein the
fourth polarizing plate and the prism are fixedly provided in an
observation light axis.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This is a Divisional of U.S. application Ser. No.
12/350,368, filed Jan. 8, 2009, which is based upon and claims the
benefit of priority from Japanese Patent Application No.
2008-001674, filed Jan. 8, 2008, the entire contents of both of
which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a microscope in which
observation methods are switchable, and specifically to a
microscope in which observation methods are switchable between a
relief contrast (RC) observation method and a differential
interference contrast observation method or polarization
observation method.
[0004] 2. Description of the Related Art
[0005] Conventionally, a microscope in which observation methods
are switchable in one microscope has been proposed and
implemented.
[0006] Here, a conventional microscope in which observation methods
are switchable will be described with reference to FIGS. 32 to 37.
FIG. 32 is a schematic side view showing an overall configuration
example of a conventional microscope, FIG. 33 is a schematic side
view showing the extracted and enlarged condenser lens part in FIG.
32, FIG. 34 is a plan view of the RC slit part in FIG. 33 seen from
the direction of the arrow X, FIG. 35 is a plan view of the slider
part in FIG. 33, FIG. 36 is a plan view of the modulator shown in
FIG. 32, and FIG. 37 is a plan view of the modulator shown in a
positional relationship with the RC slit.
[0007] The relief contrast (RC) refers to a kind of observation
methods generally called "Hoffman modulation contrast" invented by
Robert Hoffman in a microscope system for phase object observation
shown in Japanese Patent Application Laid-open (JP-A) No.
H51-29149, for example. In addition, several kinds of observation
methods based on the Hoffman modulation contrast have been
invented. Further, regarding the name of the observation method,
the method may be referred to as modulation contrast, IMC, LMC, RC,
barrel contrast other than Hoffman modulation contrast and relief
contrast. In this specification, the method is appropriately
referred to as "RC observation", which is an abbreviation of relief
contrast observation.
[0008] First, in the schematic side view showing an overall
configuration example of a microscope 100 in FIG. 32, basic
configurations of an illumination system and an observation system
will be described. The illumination light output from a light
source 2 illuminates a specimen 1 via an illumination system lens
3, a mirror 4, and a condenser lens 5 provided in an illumination
light axis L1. The specimen 1 illuminated by the illumination light
is reflected by a mirror 9 in the middle of an observation light
axis L2 and projected onto a primary image surface 10 by an
objective lens 6a and an imaging lens 8 on the observation light
axis L2. Then, the primary image is relayed by a relay lens 11 to
form a secondary image for allowing visual observation by an ocular
lens 12.
[0009] At switching to an objective lens according to magnifying
power and an observation method, a revolver 7 is revolved around
the observation light axis L2 and a desired lens 6a is inserted
into the observation light axis L2, and a focusing handle 16 is
rotationally operated. Thereby, the specimen 1 is brought into
focus by vertically moving a vertical movement guide 15 that holds
the revolver 7 relative to a microscope main body 17 (hereinafter,
sometimes referred to as an illumination optical system housing 17)
for observation. Further, when an observation is desired not
visually but using an image pickup device such as a CCD, an
observation by electronic imaging can be made by deflecting an
optical path in a direction perpendicular to the paper surface (in
a direction from the front surface to the rear surface) with a
prism 13 for imaging on the image pickup device such as a CCD.
[0010] Next, the condenser lens 5 will be described in detail with
reference to FIGS. 33 to 35. The condenser lens 5 has a turret 24
provided near its entrance pupil location and rotating about a
rotational axis 25. To the turret 24, optical devices such as a
difference interference prism (hereinafter, referred to "DIC
prism") 20 and an RC slit 21 for RC observation are detachably
fixed. By rotating the turret 24, the optical devices can be
insertably and removably positioned relative to the position on the
illumination light axis L1 by a positioning mechanism such as a
click mechanism (not shown). Further, in the turret 24, a lens 19
is fixedly provided in the illumination light axis L1.
[0011] The turret 24 has a centering mechanism with respect to the
rotation of the RC slit 21 and the light axis in the part to which
the RC slit 21 is attached as shown in FIG. 34. That is, the RC
slit 21 is configured so that it may be urged to receive pressing
force toward the center by a leaf spring 27 and the pressing force
may be received by two screws 28 separately provided at the
opposite side thereto. Thereby, the RC slit 21 can be centered with
respect to the light axis through adjustment of the position of the
RC slit 21 by turning the screws 28. Further, grooves 30 are
provided on the periphery of the RC slit 21, and the RC slit 21 can
be rotated in the horizontal plane by inserting an end of a knob 29
into one of the grooves 30 and moving the knob 29 in directions
shown by an arrow in FIG. 34.
[0012] Furthermore, a slider 26 with two types of polarizing plates
22, 23 mounted thereon is provided above the turret 24. The slider
26 is slidably provided in right and left directions indicated by
an arrow, and one of the two types of polarizing plates 22, 23 can
be insertably and removably positioned on the illumination light
axis L1 by moving the slider 26 in the arrow directions. The
positioning mechanism is not particularly shown, but a general
mechanism such as a click mechanism and stopper may be used. The
polarizing plate 22 is a polarizer for RC observation (polarizing
plate for RC observation) and the polarizing plate 23 is a
polarizer for DIC observation (a polarizing plate for DIC
observation). The polarizing plates 22, 23 can individually be
rotated by operating peripheral parts 22a, 23a protruded to the
outside, respectively, as shown in FIG. 35.
[0013] Subsequently, returning to FIG. 32, the observation system
will be described. A slider 33 with a DIC prism 31 and a polarizing
plate 32 overlapped in the light axis direction is provided below
the revolver 7. The DIC prism 31 and the polarizing plate 32 can be
insertably and removably positioned on the observation light axis
L2 at the same time by moving the slider 33 in horizontal
directions indicated by an arrow. The positioning mechanism is not
particularly shown, but a general positioning mechanism such as a
click mechanism and stopper may be used. Here, the polarizing plate
32 is an analyzer for DIC observation necessary for DIC
observation. Further, the DIC prism 31 is not particularly shown,
but is microscopically movable in the direction perpendicular to
the light axis (horizontal direction) for contrast adjustment at
DIC observation.
[0014] In such a configuration, first, the case of making DIC
observation will be described. First, the revolver 7 is
rotationally operated and the objective lens 6a for DIC is set on
the observation light axis L2 as shown in FIG. 32. Then, before
observation, adjustment is made following the procedure of (1) to
(5) because it is necessary to adjust the polarizing plates in
advance.
[0015] (1) rotationally operate the turret 24 in the condenser lens
5 for positioning a hole (not shown) on the illumination light axis
L1 so that there is no optical device on the illumination light
axis L1;
[0016] (2) slidingly operate the slider 26 in the condenser lens 5
so that the polarizer for DIC observation 23 is on the illumination
light axis L1 as shown in FIG. 33;
[0017] (3) slidingly operate the slider 33 below the revolver 7 so
that the prism for DIC 31 and the analyzer for DIC observation 32
are on the observation light axis L2;
[0018] (4) detach the ocular lens 12; and
[0019] (5) rotationally operate the polarizer for DIC observation
23 to make a crossed Nicol condition that the vibration direction
is perpendicular to the vibration direction of the analyzer for DIC
observation 32. In this regard, when the exit pupil of the
observation optical system is seen with the ocular lens 12
detached, diagonal lines are seen, and the crossed Nicol condition
occurs when the lines are the darkest. Since the vibration
direction of the analyzer for DIC observation 32 is fixed to a
previously set direction, the vibration direction of the polarizer
for DIC observation 23 becomes the direction indicated by an arrow
23b in FIG. 5 after the adjustment.
[0020] The above (1) to (5) are the prior crossed Nicol adjustment
procedure. Regarding the crossed Nicol adjustment, if the
adjustment operation is once performed, readjustment is unnecessary
unless misadjustment occurs.
[0021] Then, the ocular lens 12 is attached, the IDC prism 20
adapted to the type of the objective lens 6a is inserted into the
illumination light axis L1, the focus is brought on the specimen 1
as described above, and thereby, DIC observation visually or with
the image pickup device such as a CCD can be made.
[0022] Next, the case of making RC observation will be described.
Note that the slit adjustment before observation is also necessary
in the RC observation, and here, the outline of the slit adjustment
will be first described. In the RC slit 21 shown in FIG. 34, a
through-hole slit 21a and a polarization slit 21b are provided side
by side on a thin plate made of a material that does not transmit
illumination light. The through-hole slit 21a has a rectangular
strip shape that transmits 100% of light. The polarization slit 21b
has a rectangular strip shape to which a polarizing plate as an
analyzer for RC observation (polarizing plate for RC observation)
is attached. On the other hand, the modulator 18 having a circular
disc shape provided on the exit pupil location within the RC
objective lens 6b necessary for RC observation in the revolver 7 is
formed into three areas of areas 18a, 18b, and 18c as shown in FIG.
36. The area 18a is an area completely shielded from light, the
area 18b is an area formed to have transmittance of about 25%, and
the area 18c is an area with transmittance of 100%. Further, it is
necessary that, by the lens 19 in the condenser lens 5 and the RC
objective lens 6b, the through-hole slit 21a with transmittance of
100% be projected onto the area 18b formed to have transmittance of
about 25% of the modulator 18 and the polarization slit 21b be
projected onto the area 18c with transmittance of 100% without
running over the areas, respectively. FIG. 37 shows the states of
slit images 21a', 21b' projected onto the modulator 18 with broken
lines.
[0023] In this manner, regarding the RC slit 21 and the modulator
18, relative adjustment in the two-dimensional direction
perpendicular within the surface vertical to the light axis and the
rotational direction around the light axis is necessary.
Specifically, the adjustment is made following the procedure of (1)
to (5).
[0024] (1) under the condition that the DIC objective lens 6a shown
in FIG. 32 is on the observation light axis L2, rotationally
operate the revolver 7 to insert the RC objective lens 6b into the
illumination light axis L1;
[0025] (2) rotationally operate the turret 24 in the condenser lens
5 to insert the RC slit 21 into the illumination light axis L1;
[0026] (3) slidingly operate the slider 26 in the condenser lens 5
to insert the polarizer for RC observation 22 into the illumination
light axis L1;
[0027] (4) perform centering of the RC slit 21 and rotational
adjustment to project the through-hole slit 21a and the
polarization slit 21b onto the areas 18b, 18c of the modulator 18
without running over the areas, respectively; and
[0028] (5) adjust the contrast of the specimen 1 to be optimal by
rotating the polarizer for RC observation 22 to change the
transmittance of the polarization slit 21b of the RC slit 21.
[0029] Through the above (1) to (5), the prior adjustment operation
before RC observation is finished. By operating the slider 33 to
remove the DIC prism 31 and the analyzer for DIC observation 32
below the revolver 7 from the observation light axis L2, RC
observation visually or with the image pickup device such as a CCD
can be made.
[0030] Note that, since the size of the RC slit 21 varies according
to types of the objective lens 6b in magnifying power, numeric
aperture NA, or the like, the adjustment of (1) to (5) is necessary
with respect to each type of the objective lens 6b and the RC slit
21 to be combined. Here, only one type of the objective lens 6b and
the RC slit 21 are shown, but different types of objective lenses
6b and the RC slits 21 can be attached to the revolver 7 and the
turret 24, and they are appropriately switched for use.
[0031] The combination of the respective objective lenses 6b and
the RC slits 21 is 1:1, and thus, it is not necessary to readjust
the procedure (1) to (4) after once adjusted unless misadjustment
occurs due to an impact or the like. On the other hand, the
adjustment of the polarizer for RC observation 22 shown in the step
of (5) needs readjustment each time when the objective lens 6b is
switched. This is because the objective lens 6b is screwed and
fastened in the revolver 7. Thereby, not only in the case where the
threaded position is not specified but also in the case where it is
specified, the rotational direction of the built-in modulator 18
varies at about 5.degree., and the vibration direction of the
analyzer of the modulator 18 also varies. Therefore, when the
objective lens 6b is switched, the polarizer for RC observation 22
also needs readjustment according to the vibration direction of the
analyzer of the modulator 18.
[0032] In JP-A-2003-050353, as the configuration of the condenser
lens 5 is shown in FIG. 38, for example, the polarizer for DIC
observation 23 and the polarizer for RC observation 22 are
integrally provided on the DIC prism 20 and the RC slit 21 as
optical devices to be combined, respectively. Through switching by
the rotation of the turret 24, the polarizers and the optical
devices in pairs can be inserted and removed into and from the
illumination light axis L1 at the same time.
SUMMARY OF THE INVENTION
[0033] A microscope according to an aspect of the present invention
includes a condenser lens that is provided in an illumination light
path and in which at least one optical device is insertable into
and removable from an illumination light axis for switching
observation method; a first polarizing plate that is provided in
the same light axis as the optical device and is insertable into
and removable from the illumination light axis integrally with the
optical device; and a second polarizing plate that is provided in
the illumination light axis independently from insertion and
removal of the optical device into and from the illumination light
axis.
[0034] A microscope according to another aspect of the present
invention includes a condenser lens that is provided in an
illumination light path and in which at least one optical device is
insertable into and removable from an illumination light axis for
switching observation method; and a polarizing plate that is
provided in the illumination light axis independently from
insertion and removal of the optical device into and from the
illumination light axis, commonly uses a first polarizing plate and
a second polarizing plate, stores a position in a first vibration
direction for the first polarizing plate and a position in a second
vibration direction for the second polarizing plate, and can
selectively reproduce and hold the stored positions in the first
and second vibration directions.
[0035] A microscope according to still another aspect of the
present invention includes a polarizing plate for differential
interference or polarizing plate for polarization observation
fixedly provided in an illumination light axis; and a condenser
lens that is provided in an illumination light path and in which a
slit for relief contrast having no polarizing plate is insertable
into and removable from the illumination light axis for switching
observation method.
[0036] A microscope according to still another aspect of the
present invention includes a condenser lens that is provided in an
illumination light path and in which a slit for relief contrast
having no polarizing plate is insertable into and removable from
the illumination light axis for switching observation method; and a
polarizing plate for differential interference or polarizing plate
for polarization observation fixedly provided in an observation
light axis.
[0037] A microscope according to still another aspect of the
present invention includes an eighth polarizing plate provided in
an illumination light path; a condenser lens that is provided in a
position different from that of the eighth polarizing plate in a
light axis direction in the illumination light path and in which a
slit for relief contrast is insertable into and removable from an
illumination light axis for switching observation method; a ninth
polarizing plate for observation different from the relief contrast
observation, fixedly provided in an observation light axis; and a
depolarizer provided in a position at the ninth polarizing plate
side with respect to the slit for relief contrast.
[0038] The above and other features, advantages and technical and
industrial significance of this invention will be better understood
by reading the following detailed description of presently
preferred embodiments of the invention, when considered in
connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0039] FIG. 1 is a schematic side view showing an overall
configuration example of a microscope according to a first
embodiment of the invention;
[0040] FIG. 2 is a schematic side view showing the extracted and
enlarged condenser lens part in FIG. 1;
[0041] FIG. 3 is a perspective view showing a device example
provided in the light axis at DIC observation;
[0042] FIG. 4 is a perspective view showing a device example
provided in the light axis at RC observation;
[0043] FIG. 5 is a plan view of an RC slit in FIG. 4 seen from the
arrow X direction;
[0044] FIG. 6 is a schematic side view showing a configuration
example of a part of an illumination system of a first modification
according to the first embodiment;
[0045] FIG. 7 is a schematic side view showing a configuration
example of a condenser lens of a second modification according to
the first embodiment;
[0046] FIG. 8 is a schematic side view showing an overall
configuration example of a microscope according to a second
embodiment of the invention;
[0047] FIG. 9 is a schematic side view showing the extracted and
enlarged condenser lens part in FIG. 8;
[0048] FIG. 10 is a perspective view showing a device example
provided in the light axis at RC observation;
[0049] FIG. 11 is a schematic side view showing an overall
configuration example of a microscope according to a third
embodiment of the invention;
[0050] FIG. 12 is a schematic side view showing the extracted and
enlarged condenser lens part and analyzer for DIC observation part
in FIG. 11;
[0051] FIG. 13 is a schematic diagram showing parts of devices
provided in the light axis at RC observation developed in a
plane;
[0052] FIG. 14 is a schematic side view showing an overall
configuration example of a microscope according to a fourth
embodiment of the invention;
[0053] FIG. 15 is a schematic side view showing the extracted and
enlarged condenser lens part and analyzer for DIC observation part
in FIG. 14;
[0054] FIG. 16 is a schematic diagram showing parts of devices
provided in the light axis at RC observation developed in a
plane;
[0055] FIG. 17 is a schematic side view showing an overall
configuration example of a microscope according to a fifth
embodiment of the invention;
[0056] FIG. 18 is a schematic side view showing the extracted and
enlarged condenser lens part and analyzer for DIC observation part
in FIG. 17;
[0057] FIG. 19 is a schematic diagram showing parts of devices
provided in the light axis at RC observation developed in a
plane;
[0058] FIG. 20 is a schematic side view showing an overall
configuration example of a microscope according to a sixth
embodiment of the invention;
[0059] FIG. 21 is a schematic side view showing the extracted and
enlarged condenser lens part and analyzer for DIC observation part
in FIG. 20;
[0060] FIG. 22 is a schematic diagram showing parts of devices
provided in the light axis at RC observation developed in a
plane;
[0061] FIG. 23 is a schematic side view showing an overall
configuration example of a microscope according to a seventh
embodiment of the invention;
[0062] FIG. 24 is a schematic side view showing the extracted and
enlarged condenser lens part and analyzer for DIC observation part
in FIG. 23;
[0063] FIG. 25 is a schematic diagram showing parts of devices
provided in the light axis at RC observation developed in a
plane;
[0064] FIG. 26 is a schematic side view showing an overall
configuration example of a microscope according to an eighth
embodiment of the invention;
[0065] FIG. 27 is a schematic side view showing the extracted and
enlarged condenser lens part and analyzer for DIC observation part
in FIG. 26;
[0066] FIG. 28 is a plan view of an RC slit in FIG. 27 seen from
the arrow X direction;
[0067] FIG. 29 is a schematic side view showing an overall
configuration example of a microscope according to a ninth
embodiment of the invention;
[0068] FIG. 30 is a schematic side view showing the extracted and
enlarged condenser lens part and analyzer for DIC observation part
in FIG. 26;
[0069] FIG. 31 is a schematic side view showing a condenser lens
part of a first modification according to the ninth embodiment;
[0070] FIG. 32 is a schematic side view showing an overall
configuration example of a conventional microscope;
[0071] FIG. 33 is a schematic side view showing the extracted and
enlarged condenser lens part in FIG. 32;
[0072] FIG. 34 is a plan view of the RC slit part in FIG. 33 seen
from the direction of the arrow X;
[0073] FIG. 35 is a plan view of the slider part in FIG. 33;
[0074] FIG. 36 is a plan view of the modulator shown in FIG.
32;
[0075] FIG. 37 is a plan view of the modulator shown in a
positional relationship with the RC slit; and
[0076] FIG. 38 is a schematic side view showing the extracted and
enlarged conventional condenser lens part.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0077] Exemplary embodiments of a microscope according to the
invention will be described below with reference to the drawings.
The parts same as or the parts corresponding to the parts shown in
FIGS. 32 to 38 are shown with the same numerals and reference
characters. Various changes can be made to the invention, not
limited to the respective embodiments and modifications, without
departing from the scope of the invention.
First Embodiment
[0078] FIG. 1 is a schematic side view showing an overall
configuration example of a microscope according to a first
embodiment of the invention, FIG. 2 is a schematic side view
showing the extracted and enlarged condenser lens part in FIG. 1,
FIG. 3 is a perspective view showing a device example provided in
the light axis at DIC observation, FIG. 4 is a perspective view
showing a device example provided in the light axis at RC
observation, and FIG. 5 is a plan view of an RC slit in FIG. 4 seen
from the arrow X direction.
[0079] The overall configuration of a microscope 1A according to
the first embodiment shown in FIG. 1 is nearly the same as the
overall configuration of the conventional microscope 100 shown in
FIG. 32, but the configuration of a condenser lens 5A part is
different as shown in FIG. 2. Referring to FIG. 2, the
configuration of the condenser lens 5A of the first embodiment will
be described. In the condenser lens 5 shown in FIG. 38, both the
polarizer for RC observation 22 and the polarizer for DIC
observation 23 are provided on the turret 24, and can be inserted
into and removed from the illumination light axis L1 integrally
with the RC slit 21 and the DIC prism 20. In the condenser lens 5A
of the first embodiment, the polarizer for RC observation 22 is
provided on the turret 24 to form a pair with the RC slit 21;
however, the polarizer for DIC observation 23 is fixedly provided
in the illumination light axis L1 above the turret 24. That is, the
polarizer for RC observation 22 is provided in the same light axis
as that the RC slit 21 is on, and can be inserted into and removed
from the illumination light axis L1 integrally with the RC slit 21
by the turret 24. On the other hand, the polarizer for DIC
observation 23 is provided in the illumination light axis L1
independently from the insertion and removal of the RC slit 21 into
and from the illumination light axis L1.
[0080] Here, the polarizer for DIC observation 23 is rotatably
provided for crossed Nicol adjustment as in the conventional
example. Further, the structure of the turret 24 and the
configuration and action of the other parts of the condenser lens
5A relating to attachment and removal of the RC slit 21, rotation
adjustment, the centering adjustment mechanism, and the rotation
adjustment mechanism of the polarizer for RC observation 22 are the
same as those of the condenser lens 5.
[0081] According to the configuration, at DIC observation, the
respective devices are provided in the light axes L1, L2 as shown
in FIG. 3. Further, at RC observation, the respective devices are
provided in the light axes L1, L2 as shown in FIG. 4 by
rotationally operating the turret 24 and slidingly operating the
slider 33.
[0082] Therefore, in the first embodiment, unlike the case of the
conventional example, in the case of RC observation, not only the
polarizer for RC observation 22 but also the polarizer for DIC
observation 23 is inserted into the illumination light axis L1. In
this case, if the vibration directions of the polarizer for RC
observation 22 and the polarizer for DIC observation 23 are nearly
in the perpendicular directions, a great amount of illumination
light is lost. In this regard, in the first embodiment, as shown in
the condition at RC observation in FIG. 4, a parallel Nicol
condition that the vibration directions of the polarizer for RC
observation 22 and the polarizer for DIC observation 23 are the
same direction is set. Thereby, the loss of illumination light is
suppressed to the minimum. Note that the expression that the
vibration directions are the same direction may not mean the
directions are strictly the same, but mean they are nearly the same
direction.
[0083] In this regard, in the relationship in vibration direction
between the polarizer for RC observation 22 and the polarization
slit 21b as the analyzer for RC observation, when the total
transmittance of the aperture part of the polarization slit 21b is
around 20%, the contrast of the specimen 1 becomes appropriate.
Here, the relative angle of the vibration directions is about
10.degree. as shown in FIG. 5. Further, the threaded position of
the objective lens 6b and the revolver 7 is specified. Thereby, if
the relationship between the longitudinal direction of the
polarization slit 21b of the RC slit 21 and the vibration direction
of the polarization slit 21b is fixed irrespective of the type of
the RC slit 21, the vibration direction of the polarization slit
21b is nearly constant irrespective of the type of the RC slit 21.
Thus, as described above, both the vibration direction of the
polarizer for RC observation 22 and the polarization slit 21b are
adjusted at about 10.degree. relative to the vibration direction.
As a result, the vibration direction of the polarizer for RC
observation 22 needs no readjustment even when the type of the RC
slit 21 changes according to the magnifying power of the objective
lens 6b, and can be made nearly the same as the vibration direction
of the polarizer for DIC observation 23.
[0084] Note that, as shown in the condition at DIC observation in
FIG. 3, the vibration direction of the analyzer for DIC observation
32 is set to provide a crossed Nicol condition according to the
vibration direction of the polarizer for DIC observation 23.
[0085] According to the first embodiment, the polarizer for RC
observation 22 is mounted on the turret 24 to form a pair with the
RC slit 21, and inserted into and removed from the illumination
light axis L1 integrally with the insertion and removal of the RC
slit 21 by the rotational operation of the turret 24 that is
essential when the observation method is switched. Thereby, the
insertion and removal operation of the polarizer for RC observation
22 singly is not necessary and the number of times of operation
when the observation method is switched can be reduced. Further,
even when the magnifying power of the objective lens 6b is changed
at RC observation and the RC observation and the DIC observation
are switched, readjustment of the vibration directions of the
polarizers 22, 23 by rotational operation is not necessary.
Furthermore, the expensive polarizer for DIC observation 23 can be
provided independently from the turret 24 side and configured with
one element, and therefore, can be realized inexpensively.
Moreover, since the vibration directions of the polarizer for DIC
observation 23 and the polarizer for RC observation 22 are made the
same, even when the polarizer for DIC observation 23 is present on
the illumination light axis L1 at RC observation, the loss of
illumination light can be suppressed to the minimum. Thereby, the
polarizer for DIC observation 23 can be fixedly provided in the
illumination light axis L1 without troubles, and the insertion and
removal operation of the polarizer for DIC observation 23 can be
made unnecessary.
First Modification
[0086] FIG. 6 is a schematic side view showing a configuration
example of a part of an illumination system of the first
modification according to the first embodiment. In the first
modification, the polarizer for DIC observation 23 is not provided
in the condenser lens 5A part, but attached to the illumination
optical system housing 17 above.
[0087] According to the first modification, if DIC observation is
unnecessary, for example, the polarizer for DIC observation 23 is
not necessary to be prepared and it is economical. Further, the
modification is effective when there is no space for providing the
polarizer for DIC observation 23 in the condenser lens 5A.
Second Modification
[0088] FIG. 7 is a schematic side view showing a configuration
example of a condenser lens 50 of a second modification according
to the first embodiment. The second modification is applied to
switching of the observation method between RC observation and
polarization observation instead of switching of the observation
method between RC observation and DIC observation. That is, in
place of the polarizer for DIC observation 23 shown in FIG. 2, a
polarizer for polarization observation (polarizing plate for
polarization observation) 51 is provided on the condenser lens 50.
Further, a through hole 52 is formed in place of the DIC prism 20
in the turret 24 on the condenser lens 50, and polarization
observation can be made by the combination of the polarizer for
polarization observation 51 and the through-hole 52.
[0089] Other configurations, actions, and effects are the same as
those of the first embodiment. Since the polarizer for polarization
observation 51 is often more expensive than the polarizer for DIC
observation 23, the economical effect is much greater.
[0090] In the following embodiments, although not specifically
shown, by applying the polarizer for polarization observation 51 in
place of the polarizer for DIC observation 23 as in the second
modification, the observation method can be switched between RC
observation and polarization observation.
Second Embodiment
[0091] FIG. 8 is a schematic side view showing an overall
configuration example of a microscope according to a second
embodiment of the invention, FIG. 9 is a schematic side view
showing the extracted and enlarged condenser lens part in FIG. 8,
and FIG. 10 is a perspective view showing a device example provided
in the light axis at RC observation.
[0092] The overall configuration of a microscope 1B according to
the second embodiment shown in FIG. 8 is nearly the same as the
overall configuration of the microscope 1A shown in FIG. 1, but the
slider 33 is omitted with respect to the observation system and the
DIC prism 31 and the analyzer for DIC observation 32 are fixedly
provided in the observation light axis L2 as shown in FIG. 8.
Further, in the condenser lens 5B, a depolarizer 27 is bonded and
fixed to the lower surface (the observation optical system side) of
the through-hole slit 21a of the RC slit 21.
[0093] According to the configuration, at DIC observation, the
respective devices are provided in the light axes L1, L2 as shown
in the above described FIG. 3. On the other hand, at RC
observation, the respective devices are provided in the light axes
L1, L2 as shown in FIG. 10 by rotationally operating the turret 24.
That is, at the RC observation, the DIC prism 31 and the analyzer
for DIC observation 32 also remain provided in the observation
light axis L2. In this regard, the analyzer for DIC observation 32
is in a crossed Nicol condition with the vibration direction of the
polarizer for RC observation 22, and the loss of the illumination
light passing through the through-hole slit 21a of the RC slit 21
becomes extremely great. However, the depolarizer 27 is provided on
the lower surface of the through-hole slit 21a and the polarization
state of the illumination light passing through the through-hole
slit 21a is resolved, and thus, the loss in the amount of light can
be suppressed in the analyzer for DIC observation 32 part. Thereby,
no trouble is caused when the DIC prism 31 and the analyzer for DIC
observation 32 are fixedly provided in the observation light axis
L2, the insertion and removal operation is unnecessary when the
observation method is switched, and the number of times of the
insertion and removal operation can be further reduced.
Third Embodiment
[0094] FIG. 11 is a schematic side view showing an overall
configuration example of a microscope according to a third
embodiment of the invention, FIG. 12 is a schematic side view
showing the extracted and enlarged condenser lens part and analyzer
for DIC observation part in FIG. 11, and FIG. 13 is a schematic
diagram showing parts of devices provided in the light axis at RC
observation developed in a plane.
[0095] The overall configuration of a microscope 1C according to
the third embodiment shown in FIG. 11 is nearly the same as the
overall configuration of the microscope 1B shown in FIG. 8, but the
configuration of a condenser lens 5C part is different as shown in
FIG. 12. Referring to FIG. 12, the configuration of the condenser
lens 5C of the third embodiment will be described. In the third
embodiment, the polarizer for DIC observation 23 is provided on the
slider 26 together with a through hole 28 so that the insertion
into and removal from the illumination light axis L1 can be
performed independent from the turret 24 side.
[0096] In such a configuration, at RC observation, the RC slit 21
and the polarizer for RC observation 22 are inserted into the
illumination light axis L1 by rotationally operating the turret 24
and the through hole 28 is inserted into the illumination light
axis L1 by slidingly operating the slider 26. Thereby, the
observation condition in which the polarizer for DIC observation 23
is not present on the illumination light axis L1 can be made. Thus,
the loss of illumination light can be further reduced at RC
observation.
[0097] Here, in the third embodiment, as in the second embodiment,
the slider 33 is omitted with respect to the observation system and
the DIC prism 31 and the analyzer for DIC observation 32 are
fixedly provided in the observation light axis L2. Further, for DIC
observation, the vibration directions of the polarizer for DIC
observation 23 and the analyzer for DIC observation 32 are set in a
crossed Nicol condition. In addition, in the third embodiment, as
schematically shown in FIG. 13, a parallel Nicol condition that the
vibration directions of the analyzer for DIC observation 32 and the
polarizer for RC observation 22 are the same direction is set. Note
that the expression that the vibration directions are the same
direction may not mean the directions are strictly the same, but
mean they are nearly the same direction. Furthermore, with the
setting change of the vibration direction of the polarizer for RC
observation 22, the vibration direction of the polarization slit
21b of the RC slit 21 is also adjusted and changed in settings as
shown in FIG. 13 (the modulator 18 is also adjusted according
thereto).
[0098] As described above, according to the third embodiment, the
vibration directions of the analyzer for DIC observation 32 and the
polarizer for RC observation 22 are in the parallel Nicol
condition, and the loss of the illumination light passing through
the through-hole slit 21a of the RC slit 21 can be suppressed to an
extremely small amount. Thereby, the DIC prism 31 and the analyzer
for DIC observation 32 are fixedly provided in the observation
light axis L2, the insertion and removal operation can be made
unnecessary when the observation method is switched, and the number
of times of the insertion and removal operation can be reduced.
Fourth Embodiment
[0099] FIG. 14 is a schematic side view showing an overall
configuration example of a microscope according to a fourth
embodiment of the invention, FIG. 15 is a schematic side view
showing the extracted and enlarged condenser lens part and analyzer
for DIC observation part in FIG. 14, and FIG. 16 is a schematic
diagram showing parts of devices provided in the light axis at RC
observation developed in a plane.
[0100] The overall configuration of a microscope 1D according to
the fourth embodiment shown in FIG. 14 is nearly the same as the
overall configuration of the microscope 1B shown in FIG. 8, but the
configuration of a condenser lens 5D part is different as shown in
FIG. 15. Referring to FIG. 15, the configuration of the condenser
lens 5D of the fourth embodiment will be described.
[0101] In the fourth embodiment, in the condenser lens 5D, only the
DIC prism 20 and the RC slit 21 are mounted on the turret 24 and
one common polarizer 34 is provided at the upper part in the
position on the illumination light axis L1. The common polarizer 34
commonly uses the functions of the polarizer for DIC observation 23
and the polarizer for RC observation 22. The common polarizer 34 is
configured to use a click mechanism to store the position (angle)
in the first vibration direction and the position (angle) in the
second vibration direction and selectively reproduce and hold the
stored positions in the first and second vibration directions.
Here, the first vibration direction is for the polarizer for RC
observation 22, and the second vibration direction is for the
polarizer for DIC observation 23.
[0102] Hereinafter, the structure for storing the positions
(angles) in the first and second vibration directions of the common
polarizer 34 using the click mechanism and reproducing and holding
the positions will be described by referring to FIG. 15. The common
polarizer 34 is bonded and secured to an annular polarizer frame
35. The polarizer frame 35 is rotatably held while its motion in
the thrust direction is regulated relative to an annular middle
frame 36 that is slightly larger. Further, the middle frame 36 is
rotatably held while its motion in the thrust direction is
regulated relative to an annular outer frame 38 that is further
slightly larger. A threaded part 37a of a knob 37 is screwed into
the polarizer frame 35 via long holes 36a, 38a that are longer in
the circumferential direction provided on the outer circumferential
surfaces of the middle frame 36 and the outer frame 38. By moving
the knob 37 while the thread is loosen, the polarizer frame 35
becomes rotatable relative to the middle frame 36. When the thread
37 of the knob is completely screwed, the polarizer frame 35 cannot
rotate, but is fixed relative to the middle frame 36 in the
fastened condition.
[0103] Further, if the knob 37 is moved when the thread of the knob
is completely screwed, the middle frame 36 rotates relative to the
outer frame 38, and can be positioned by a groove 36b formed in a
part of the middle frame 36 and a click mechanism 40a including a
coil spring and a ball provided in the outer frame 38. Furthermore,
by a groove 39a formed in a part of an annular click frame 39
fitted at the outer circumferential surface side of the middle
frame 36 and a click mechanism 40b including a coil spring and a
ball provided in the outer frame 38, the click frame 39 is
temporarily fixed to the outer frame 38. Thereby, if the knob 37 is
moved when the thread of the knob 37 is completely screwed, the
middle frame 36 rotates relative to the outer frame 38, and becomes
rotatable relative to the click frame 39.
[0104] In this state, when a screw 48 screwed into the click frame
39 is fastened via a long hole 38b provided on the outer
circumferential surface of the outer frame 38, the middle frame 36
and the click frame 39 integrally rotate. Further, by the groove
39a of the click frame 39 and the click mechanism 40b including the
coil spring and the ball provided in the outer frame 38, the middle
frame 36 and the outer frame 38 can be positioned.
[0105] According to such a configuration, crossed Nicol adjustment
for DIC observation is performed with the knob 37 loosened, and the
knob 37 is screwed and fastened so that the position (angle) in the
vibration direction for the common polarizer 34 to function as the
polarizer for DIC observation 23 may be stored. Furthermore,
polarizer adjustment at RC observation is performed by rotationally
operating the knob 37, and the screw 48 is fastened so that the
position (angle) in the vibration direction for the common
polarizer 34 to function as the polarizer for RC observation 22 may
be stored.
[0106] Accordingly, at DIC observation and RC observation,
regarding the common polarizer 34, the position of crossed Nicol
for DIC observation and the position in the vibration direction of
the polarizer for RC observation can be selectively reproduced and
held by rotationally operating the knob 37 with the click
mechanisms 40a or 40b.
[0107] Thus, according to the fourth embodiment, when the
observation method is switched, the positions in two vibration
directions set in the common polarizer 34 may be selectively
reproduced and held, and the insertion and removal operation into
the illumination light axis L1 is unnecessary and the number of
times of the insertion and removal operation can be reduced.
Further, the positions in two vibration directions set in the
common polarizer 34 are reproducibly and holdably stored using the
click mechanisms 40a, 40b, and switching of the vibration direction
of the common polarizer 34 when the observation method is switched
can be easily performed. In addition, DIC observation and RC
observation can be made with one common polarizer 34, and the
configuration can be inexpensively made.
[0108] Here, in the fourth embodiment, as in the third embodiment,
the slider 33 is omitted with respect to the observation system and
the DIC prism 31 and the analyzer for DIC observation 32 are
fixedly provided in the observation light axis L2. Further, for DIC
observation, the position in the vibration direction in which the
common polarizer 34 functions as the polarizer for DIC observation
23 and the position in the vibration direction of the analyzer for
DIC observation 32 are set in a crossed Nicol condition.
Furthermore, as schematically shown in FIG. 16, a parallel Nicol
condition that the position in the vibration direction of the
analyzer for DIC observation 32 and the position in the vibration
direction in which the common polarizer 34 functions as the
polarizer for RC observation 22 are in the same direction is set.
Note that the expression that the vibration directions are the same
direction may not mean the directions are strictly the same, but
mean they are nearly the same direction. Furthermore, with the
setting change of the vibration direction of the polarizer for RC
observation 22, the vibration direction of the polarization slit
21b of the RC slit 21 is also adjusted and changed in settings as
shown in FIG. 13 (the modulator 18 is also adjusted according
thereto).
[0109] As described above, according to the fourth embodiment, the
position in the vibration direction of the analyzer for DIC
observation 32 and the position in the vibration direction in which
the common polarizer 34 functions as the polarizer for RC
observation 22 are in the parallel Nicol condition. Accordingly,
the loss of the illumination light passing through the through-hole
slit 21a of the RC slit 21 can be suppressed to an extremely small
amount. Thereby, the DIC prism 31 and the analyzer for DIC
observation 32 are fixedly provided in the observation light axis
L2, the insertion and removal operation can be made unnecessary
when the observation method is switched, and the number of times of
the insertion and removal operation can be reduced.
Fifth Embodiment
[0110] FIG. 17 is a schematic side view showing an overall
configuration example of a microscope according to a fifth
embodiment of the invention, FIG. 18 is a schematic side view
showing the extracted and enlarged condenser lens part and analyzer
for DIC observation part in FIG. 17, and FIG. 19 is a schematic
diagram showing parts of devices provided in the light axis at RC
observation developed in a plane.
[0111] The overall configuration of a microscope 1E according to
the fifth embodiment shown in FIG. 17 is nearly the same as the
overall configuration of the microscope 1D shown in FIG. 14, but
the configuration of a condenser lens 5E part is different as shown
in FIG. 18. Referring to FIG. 18, the configuration of the
condenser lens 5E of the fifth embodiment will be described.
[0112] In the fifth embodiment, in the condenser lens 5E, only the
DIC prism 20 and the RC slit 21 are mounted on the turret 24 and
one common polarizer 34 is provided at the upper part in the
position on the illumination light axis L1. The common polarizer 34
commonly uses the functions of the polarizer for DIC observation 23
and the polarizer for RC observation 22. The common polarizer 34 is
configured, under the electric control using a motor 43, to
automatically store the position (angle) in the first vibration
direction and the position (angle) in the second vibration
direction and selectively reproduce and hold the stored positions
in the first and second vibration directions. Here, the first
vibration direction is for the polarizer for RC observation 22, and
the second vibration direction is for the polarizer for DIC
observation 23.
[0113] Hereinafter, the configuration for storing the positions
(angles) of the first and second vibration directions of the common
polarizer 34 under the electric control using a motor 43 and
reproducing and holding the positions will be described by
referring to FIG. 18. First, the common polarizer 34 is bonded and
secured to an annular polarizer frame 44 that is rotatably
provided. A gear 44a is provided on the outer circumferential
surface of the polarizer frame 44, meshed with a gear 45 fixed to
the shaft of the motor 43, and the polarizer frame 44 is rotatable
by the rotational drive of the motor 43. Here, the motor 43
includes a rotational angle detection mechanism of a rotary encoder
or the like, and the rotational angle can be detected. Further, a
control unit 42 for controlling the drive of the motor 43 stores
each position (angle) in the vibration direction adjusted and set
so that the common polarizer 34 as described in the fourth
embodiment may function as the polarizer for DIC observation or the
polarizer for RC observation. In addition, as shown in FIG. 17, the
revolver 7 is also configured rotatable by the motor 41. The
operation of the motor 41 is also controlled by the control unit
42.
[0114] Thereby, the control unit 42 determines what type of
objective lens is inserted into the observation light axis L2 based
on the drive of the motor 41. Then, the control unit 42
automatically reproduces and holds the position (angle) in the
vibration direction of the common polarizer 34 that has been
properly set in advance through the drive-control by the motor 43
according to the type of inserted objective lens.
[0115] According to such a configuration, in the fifth embodiment,
when the objective lens is switched, the common polarizer 34 is
reproduced and held by the motor 43 to be in the proper position
(angle) in the vibration direction concurrently with the switching.
Thus, observation according to a desired observation method can be
made only by rotational operation of the turret 24 that is
essential for the switching of the observation method to insert the
DIC prism 20 and the RC slit 21 that are adapted to the magnifying
power of the objective lens and the observation method into the
illumination light axis L1.
[0116] Therefore, according to the fifth embodiment, when the
observation method is switched, the positions in two vibration
directions set in the common polarizer 34 may be selectively
reproduced and held, and the insertion and removal operation of the
common polarizer 34 into the illumination light axis L1 is
unnecessary and the number of times of the insertion and removal
operation can be reduced. Further, also the rotational operation of
the common polarizer 34 can be automatically conducted by the motor
43, and no manual operation for the common polarizer 34 is
necessary. Furthermore, DIC observation and RC observation can be
made with one common polarizer 34, and the configuration can be
inexpensively made.
[0117] Here, in the fifth embodiment, as in the fourth embodiment,
the slider 33 is omitted with respect to the observation system and
the DIC prism 31 and the analyzer for DIC observation 32 are
fixedly provided in the observation light axis L2. Further, for DIC
observation, the position in the vibration direction in which the
common polarizer 34 functions as the polarizer for DIC observation
23 and the position in the vibration direction of the analyzer for
DIC observation 32 are set in a crossed Nicol condition.
Furthermore, as schematically shown in FIG. 19, a parallel Nicol
condition that the position in the vibration direction of the
analyzer for DIC observation 32 and the position in the vibration
direction in which the common polarizer 34 functions as the
polarizer for RC observation 22 are in the same direction is set.
Note that the expression that the vibration directions are the same
direction may not mean the directions are strictly the same, but
mean they are nearly the same direction. Furthermore, with the
setting change of the vibration direction of the polarizer for RC
observation 22, the vibration direction of the polarization slit
21b of the RC slit 21 is also adjusted and changed in settings as
shown in FIG. 19 (the modulator 18 is also adjusted according
thereto).
[0118] As described above, according to the fifth embodiment, the
position in the vibration direction of the analyzer for DIC
observation 32 and the position in the vibration direction in which
the common polarizer 34 functions as the polarizer for RC
observation 22 are in the parallel Nicol condition. Accordingly,
the loss of the illumination light passing through the through-hole
slit 21a of the RC slit 21 can be suppressed to an extremely small
amount. Thereby, the DIC prism 31 and the analyzer for DIC
observation 32 are fixedly provided in the observation light axis
L2, and the insertion and removal operation is unnecessary when the
observation method is switched. Accordingly, the necessary
insertion and removal operation by an operator is only the
rotational operation of the turret 24 that is essential for the
switching of the observation method.
Sixth Embodiment
[0119] FIG. 20 is a schematic side view showing an overall
configuration example of a microscope according to a sixth
embodiment of the invention, FIG. 21 is a schematic side view
showing the extracted and enlarged condenser lens part and analyzer
for DIC observation part in FIG. 20, and FIG. 22 is a schematic
diagram showing parts of devices provided in the light axis at RC
observation developed in a plane.
[0120] The overall configuration of a microscope 1F according to
the sixth embodiment shown in FIG. 20 is nearly the same as the
overall configuration of the microscope 100 shown in FIG. 32, but
the slider 33 is omitted with respect to the observation system and
the DIC prism 31 and the analyzer for DIC observation 32 are
fixedly provided in the observation light axis L2 as shown in FIG.
20.
[0121] The component elements of a condenser lens 5F part are the
same as those of the condenser lens 5 shown in FIG. 33. Here, for
DIC observation, the vibration directions of the polarizer for DIC
observation 23 and the analyzer for DIC observation 32 are set in a
crossed Nicol condition. In addition, in the sixth embodiment, as
schematically shown in FIG. 22, a parallel Nicol condition that the
vibration directions of the analyzer for DIC observation 32 and the
polarizer for RC observation 22 are the same direction is set. Note
that the expression that the vibration directions are the same
direction may not mean the directions are strictly the same, but
mean they are nearly the same direction. Furthermore, with the
setting change of the vibration direction of the polarizer for RC
observation 22, the vibration direction of the polarization slit
21b of the RC slit 21 is also adjusted and changed in settings as
shown in FIG. 22 (the modulator 18 is also adjusted according
thereto).
[0122] As described above, according to the sixth embodiment, the
vibration directions of the analyzer for DIC observation 32 and the
polarizer for RC observation 22 are in the parallel Nicol
condition, and the loss of the illumination light passing through
the through-hole slit 21a of the RC slit 21 can be suppressed to an
extremely small amount. Thereby, the DIC prism 31 and the analyzer
for DIC observation 32 are fixedly provided in the observation
light axis L2, the insertion and removal operation can be made
unnecessary when the observation method is switched, and the number
of times of the insertion and removal operation can be reduced.
Seventh Embodiment
[0123] FIG. 23 is a schematic side view showing an overall
configuration example of a microscope according to a seventh
embodiment of the invention, FIG. 24 is a schematic side view
showing the extracted and enlarged condenser lens part and analyzer
for DIC observation part in FIG. 23, and FIG. 25 is a schematic
diagram showing parts of devices provided in the light axis at RC
observation developed in a plane.
[0124] The overall configuration of a microscope 1G according to
the seventh embodiment shown in FIG. 23 is nearly the same as the
overall configuration of the microscope 100 shown in FIG. 32, but
the slider 33 is omitted with respect to the observation system and
the DIC prism 31 and the analyzer for DIC observation 32 are
fixedly provided in the observation light axis L2 as shown in FIG.
23.
[0125] The component elements of a condenser lens 5G part are the
same as those of the condenser lens 5 shown in FIG. 38. Here, for
DIC observation, the vibration directions of the polarizer for DIC
observation 23 and the analyzer for DIC observation 32 are set in a
crossed Nicol condition. In addition, in the seventh embodiment, as
schematically shown in FIG. 25, a parallel Nicol condition that the
vibration directions of the analyzer for DIC observation 32 and the
polarizer for RC observation 22 are the same direction is set. Note
that the expression that the vibration directions are the same
direction may not mean the directions are strictly the same, but
mean they are nearly the same direction. Furthermore, with the
setting change of the vibration direction of the polarizer for RC
observation 22, the vibration direction of the polarization slit
21b of the RC slit 21 that forms a pair on the turret 24 is also
adjusted and changed in settings as shown in FIG. 25 (the modulator
18 is also adjusted according thereto).
[0126] As described above, according to the seventh embodiment, the
vibration directions of the analyzer for DIC observation 32 and the
polarizer for RC observation 22 are in the parallel Nicol
condition, and the loss of the illumination light passing through
the through-hole slit 21a of the RC slit 21 can be suppressed to an
extremely small amount. Thereby, the DIC prism 31 and the analyzer
for DIC observation 32 are fixedly provided in the observation
light axis L2, the insertion and removal operation can be made
unnecessary when the observation method is switched, and the number
of times of the insertion and removal operation can be reduced.
Eighth Embodiment
[0127] FIG. 26 is a schematic side view showing an overall
configuration example of a microscope according to an eighth
embodiment of the invention, FIG. 27 is a schematic side view
showing the extracted and enlarged condenser lens part in FIG. 26,
and FIG. 28 is a plan view of an RC slit in FIG. 27 seen from the
arrow X direction.
[0128] The overall configuration of a microscope 1H according to
the eighth embodiment shown in FIG. 26 is nearly the same as the
overall configuration of the microscope 1B shown in FIG. 1, but the
configuration of a condenser lens 5H part is different as shown in
FIG. 26.
[0129] Here, referring to FIGS. 27 and 28, the configuration of the
condenser lens 5H part will be described. In the eighth embodiment,
in the illumination optical system, an RC slit 46 having only a
through-hole slit 46a with a rectangular strip shape that transmits
100% of light but having no polarizing plate (polarizing slit) is
used in place of the RC slit 21 as shown in FIG. 28. Since no
polarizing plate is used when RC observation is made using the RC
slit 46, the polarizer for RC observation 22 is omitted. Thereby,
in the condenser lens 5H, the DIC prism 20 and the RC slit 46 are
mounted on the turret 24 and provided insertably into and removably
from the illumination light axis L1.
[0130] The RC observation method using the RC slit 46 having only
the through-hole slit 46a has been known according to
JP-A-2004-109919, for example. Schematically, the method uses the
through-hole slit 46a in the rectangular strip shape of the RC slit
46 to run over by about 10% of the area 18c with transmittance of
100% of the modulator 18 to adjust the contrast of the specimen
according to the degree of running over.
[0131] In this case, regarding the RC slit 46, as in the first
embodiment, rotation and centering adjustment is performed and then
the position of the through-hole slit 46a is displaced using the
centering mechanism for contrast adjustment.
[0132] According to the eighth embodiment, since no polarizing
plate (polarizer) is used at RC observation, if the polarizer for
DIC observation 23 is present on the illumination light axis L1 at
RC observation, the loss in brightness is little. Accordingly, at
switching from DIC observation to RC observation, the insertion and
removal operation of the polarizer for DIC observation 23 into and
from the illumination light axis L1 is unnecessary, and the number
of times of the insertion and removal operation can be reduced.
Further, when the magnifying power of the objective lens 6b is
changed in RC observation, if RC slits 46 corresponding to the
respective magnifying power of the objective lenses 6b are once
adjusted, readjustment is not necessary. The DIC prism 31 and the
analyzer for DIC observation 32 can be insertably and removably
positioned into and from the observation light axis L2 as shown by
an arrow in FIG. 26 to prevent the loss in the mount of light that
transmits the RC slit 46 at RC observation.
Ninth Embodiment
[0133] FIG. 29 is a schematic side view showing an overall
configuration example of a microscope according to a ninth
embodiment of the invention, and FIG. 30 is a schematic side view
showing the extracted and enlarged condenser lens part in FIG.
29.
[0134] The overall configuration of a microscope 1I according to
the ninth embodiment shown in FIG. 29 is nearly the same as the
overall configuration of the microscope 1B shown in FIG. 8, but the
configuration of a condenser lens 5I part is different as shown in
FIG. 30. Further, the slider 33 is omitted with respect to the
observation system and the DIC prism 31 and the analyzer for DIC
observation 32 are fixedly provided in the observation light axis
L2 as in FIG. 8.
[0135] Here, referring to FIG. 30, the configuration of the
condenser lens 5I part will be described. In the ninth embodiment,
as in the condenser lens 5H of the above described eighth
embodiment, in the illumination optical system, an RC slit 46
having only a through-hole slit 46a with a rectangular strip shape
that transmits 100% of light but having no polarizing plate
(polarizing slit) is used in place of the RC slit 21 as shown in
FIG. 28. Since no polarizing plate is used when RC observation is
made using the RC slit 46, the polarizer for RC observation 22 is
omitted. Thereby, in the condenser lens 5I, the DIC prism 20 and
the RC slit 46 are mounted on the turret 24 and provided insertably
into and removably from the illumination light axis L1, and only
the polarizer for DIC observation 23 is fixedly provided in the
illumination light axis L1 as a polarizer. Further, in the
condenser lens 5I, a depolarizer 47 is bonded and fixed to the
lower surface (the observation optical system side) of the
through-hole slit 46a of the RC slit 46.
[0136] Also, in this case, regarding the RC slit 46, as in the
first embodiment, rotation and centering adjustment is performed
and then the position of the through-hole slit 46a is displaced
using the centering mechanism for contrast adjustment.
[0137] According to the ninth embodiment, since no polarizing plate
(polarizer) is used at RC observation, if the polarizer for DIC
observation 23 exists on the illumination light axis L1 at RC
observation, the loss in brightness is little. Accordingly, at
switching from DIC observation to RC observation, the insertion and
removal operation of the polarizer for DIC observation 23 to and
from the illumination light axis L1 is unnecessary, and the number
of times of the insertion and removal operation can be reduced.
Further, when the magnifying power of the objective lens 6b is
changed in RC observation, if RC slits 46 corresponding to the
respective objective lenses 6b are once adjusted, readjustment is
not necessary.
[0138] Further, in the ninth embodiment, in the observation optical
system, the DIC prism 31 and the analyzer for DIC observation 32
also remain provided in the observation light axis L2. In this
regard, the analyzer for DIC observation 32 is in a crossed Nicol
condition with the vibration direction of the polarizer for DIC
observation 23, and the loss of the illumination light passing
through the through-hole slit 46a of the RC slit 46 becomes
extremely great. However, the depolarizer 47 is provided on the
lower surface of the through-hole slit 46a and the polarization
state of the illumination light passing through the through-hole
slit 46a is resolved, and thus, the loss in the amount of light can
be suppressed in the analyzer for DIC observation 32 part. Thereby,
the DIC prism 31 and the analyzer for DIC observation 32 are
fixedly provided in the observation light axis L2 and the insertion
and removal operation can be made unnecessary when the observation
method is switched. Therefore, the necessary insertion and removal
operation is only the rotational operation of the turret 24 that is
essential for the switching of the observation method.
First Modification
[0139] FIG. 31 is a schematic side view showing a condenser lens
part of a first modification according to the ninth embodiment. In
the condenser lens 5J of the first modification, also the polarizer
for DIC observation 23 forming a pair with the DIC prism 20 is
integrally provided on the turret 24. Thereby, when the RC slit 46
is inserted into the illumination light axis L1 for RC observation,
the depolarizer 47 is unnecessary because the polarizer for DIC
observation 23 comes off the illumination light axis L1.
[0140] Additional advantages and modifications will readily occur
to those skilled in the art. Therefore, the invention in its
broader aspects is not limited to the specific details and
representative embodiments shown and described herein. Accordingly,
various modifications may be made without departing from the spirit
or scope of the general inventive concept as defined by the
appended claims and their equivalents.
* * * * *