U.S. patent number RE34,214 [Application Number 07/288,287] was granted by the patent office on 1993-04-06 for method and apparatus for microphotometering microscope specimens.
This patent grant is currently assigned to Molecular Dynamics, Inc.. Invention is credited to Nils R. D. Aslund, Kjell S. Carlsson.
United States Patent |
RE34,214 |
Carlsson , et al. |
April 6, 1993 |
Method and apparatus for microphotometering microscope
specimens
Abstract
A method of microphotometering individual volume elements of a
microscope specimen 10, comprising generating a luminous dot or
cursor and progressively illuminating a plurality of part elements
in the focal plane 11 of the microscope through the specimen. The
mutual position between the specimen and the focal plane is then
changed and a plurality of part elements in the focal plane are
illuminated. Reflected and/or fluorescent light and transmitted
light respectively created by the illumination is collected,
detected and stored for generating a three-dimensional image of
that part of the specimen composed of the volume elements.
Illumination of multiples of part elements is implemented by
deflecting the cursor and/or by moving the specimen. The change in
the relative mutual position between the specimen and the focal
plane of the microscope is effected either by displacing the
specimen or the objective. Apparatus for carrying out the method
include a specimen table 301, a microscope objective and light
source 31-32-33. The table or the objective are arranged for
stepwise movement along the main axis of the microscope
synchronously with punctilinear light scanning of the specimen. The
table is arranged for stepwise movement at right angles to the main
axis and/or the light source is arranged for deflection over the
focal plane 21 through the specimen.
Inventors: |
Carlsson; Kjell S. (Vallentuna,
SE), Aslund; Nils R. D. (Stockholm, SE) |
Assignee: |
Molecular Dynamics, Inc.
(Sunnyvale, CA)
|
Family
ID: |
20355166 |
Appl.
No.: |
07/288,287 |
Filed: |
December 21, 1988 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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Reissue of: |
703842 |
Feb 21, 1985 |
04631581 |
Dec 23, 1986 |
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Foreign Application Priority Data
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Mar 15, 1984 [SE] |
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8401458 |
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Current U.S.
Class: |
348/79; 348/141;
356/308; 356/318 |
Current CPC
Class: |
G01N
21/5911 (20130101); G02B 21/002 (20130101); G02B
21/0096 (20130101); G01N 21/474 (20130101); G01N
21/6456 (20130101); G01N 2201/1087 (20130101) |
Current International
Class: |
G02B
21/00 (20060101); G01N 21/59 (20060101); H04N
007/18 () |
Field of
Search: |
;358/93,106,107,89
;350/511 ;356/226,301,308,318 ;250/234 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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0112401 |
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Jul 1984 |
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EP |
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2360197 |
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Jun 1975 |
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DE |
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2655525 |
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Jun 1978 |
|
DE |
|
3243890 |
|
Jun 1983 |
|
DE |
|
2184321 |
|
Jun 1987 |
|
GB |
|
Other References
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Carlsson, A. Liljeborg, L. Majlof, Physics IV, Royal Institute of
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Microcomputer", I. J. Cox, C. J. R. Sheppard, 2219 Applied Optics
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Sheppard, D. K. Hamilton, I. J. Cox, Proc. R. Soc. Lond. A, vol.
387, pp. 171-186. .
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Agard, John W. Sedat, Nature, vol. 302, Apr. 21, 1983, pp. 676-681.
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"Dynamic Focusing in the Confocal Scanning Microscope", T. Wilson
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pp. 139-143. .
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Jena", Shura Agadshanyan, Peter Dopel, Peter Gretscher, Werner
Witsack, JR 6, 1977, pp. 270-276. .
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Inc..
|
Primary Examiner: Britton; Howard W.
Attorney, Agent or Firm: Schneck & McHugh
Claims
I claim:
1. A method for microphotometering and subsequent image combination
by generating with the aid of a convergent light beam a luminous
dot or cursor in the focal plane (11) of a microscope (30), fitting
the cursor to a plurality of part elements in the specimen (10),
and collecting light created by the luminous cursor and the
specimen (10), detecting the collected light and producing
corresponding electric signals, characterized by changing the
mutual position between the specimen (10) and the focal plane (11)
and re-fitting the luminous cursor to a plurality of part elements
in the specimen (10); repeating stepwise changes in the mutual
position between the specimen (10) and the focal plane (11) and,
subsequent to each such change, again fitting or matching the
luminous cursor to a plurality of part elements in the specimen;
collecting the light created by the luminous cursor and part
elements in the specimen (10) and screening-off any disturbing
light created synchronously from adjacent (above, beneath, beside)
part elements in the specimen (10); detecting the thus collected
light and storing measurement values obtained through said
detection, said storage optionally being effected synchronously
with the matching of the luminous cursor with part elements in the
specimen (10) and with the changes in the mutual position between
the specimen (10) and the focal plane (11), said measurement values
being representative of locations in various layers through the
specimen; and combining the measurement values from locations in a
plurality of layers, representative of a given volume of the
specimen, in dependence upon a planned/desired analysis of the
specimen.[...]. .Iadd.in a manner yielding a projected
representation from a desired angle of at least a portion of the
specimen. .Iaddend.
2. A method according to claim 1, characterized in that matching of
the luminous cursor with a plurality of part elements in the
specimen (10) is effected by .[.delinking.]. .Iadd.deflecting
.Iaddend.stepwise the convergent light beam in two dimensions (x-
and y-directions); and in that the stepwise change in the mutual
position between the specimen (10) and the focal plane .[.(10).].
.Iadd.(11) .Iaddend.of the microscope is effected by moving
stepwise the microscope object table (301) on which the specimen is
placed (z-direction).
3. A method according to claim 1, characterized in that matching of
the luminous cursor with a plurality of part elements in the
specimen (10) is effected by relative rapid stepwise deflection of
the convergent light beam in one dimension (y-direction), and by
relatively slow stepwise displacement of the microscope object
table (401) on which the specimen (10) is placed in a further
dimension (x-direction); and in that the stepwise change in the
mutual position between the specimen (10) and the microscope focal
plane .[.(10).]. .Iadd.(11).Iaddend.is effected by stepwise
displacement of the microscope object table (401)
(z-direction).
4. A method according to claim 1, characterized in that matching of
the luminous cursor with a plurality of part elements in the
specimen (10) is effected by stepwise displacement of the
microscope object table (501) along a surface (x-y-plane)
perpendicular to the main axis of the microscope; and in that the
stepwise change in the mutual position between the specimen (10)
and the focal plane of the microscope (50) is effected by stepwise
displacement of the object table (501) of the microscope (50)
(z-direction).
5. A method according to claim 4, characterized in that collection
of light (reflected fluorescent light) created by the luminous
cursor and part elements in the specimen (10) is effected on that
side of the object table (501) on which the microscope (50) is
placed.
6. A method according to claim 5, characterized in that collection
of light (transmitted light) created by the luminous cursor and
part elements in the specimen (10) is effected on the opposite side
of the object table (661) to that on which the microscope (60) is
placed.
7. Apparatus for the microphotometering and subsequent image
combination of a specimen, comprising a microscope (30) having an
object table (301), a light source (31-32-33), a detector (35) and
a control and data-collecting assembly (36), characterized in that
the object table (301) of the microscope (30) is arranged for
stepwise movement in a direction corresponding to the main axis
(z-direction) of the microscope (30), said movement being
controlled and effected in response to guide pulses from the
control and data-collecting assembly (36) in synchronization with
the scanning of the light source (31-32-33) of part elements in a
microscope specimen (10) placed on the object table (301); and in
that the apparatus also includes .[.equipment.]. .Iadd.means
.Iaddend.(37, 38,39) for storing, processing and visually
displaying data originating from said measurement values.[...].
.Iadd.in a manner yielding a projected representation from a
desired angle of at least a portion of the specimen. .Iaddend.
8. Apparatus according to claim 7, characterized in that the object
table (401) of the microscope (40) is arranged for stepwise
movement in a first direction (x-direction) at right angles to the
main axis of the microscope (z-direction); in that the light source
(41-42-43) is arranged to scan stepwise part elements in the
specimen in a further direction (y-direction) at right angles to
the main axis of the microscope (z-direction); and in that
movements of the object table (401) and the light source (41-42-43)
are co-ordinated for scanning a first plurality of part elements in
a first plane through the specimen, and then of a second plurality
of part elements in a second plane through said specimen, said
second plane extending plane parallel with the first plane, etc.
for scanning the whole specimen.
9. Apparatus according to claim 7, characterized in that the object
table (501) of the microscope (50) is arranged for relatively slow
stepwise movement in a first direction (x-direction) at right
angles to the main axis (z-direction) of the microscope (50) and in
a relatively rapid stepwise movement in a further direction
(y-direction) at right angles to the main axis (z-direction) of the
microscope, wherewith movements of the object table (501) in planes
at right angles to the main axis of the microscope and parallel
with the main axis are co-ordinated through control pulses from the
control and data-collecting assembly (56) for scanning part element
after part element through the whole of the specimen. .Iadd.
10. A method for microphotometering a 3-dimensional specimen using
a light detection apparatus, the specimen defining a plurality of
layers, each layer defining a plurality of part elements, and the
detection apparatus defining a focal plane, the method comprising
the following steps:
(a) generating a cursor of light in the focal plane;
(b) positioning at least one of (1) the focal plane and (2) the
specimen such that a desired one of the layers lies in the focal
plane;
(c) selecting at least one of the part elements in the selected
layer;
(d) positioning at least one of (1) the cursor and (2) the specimen
to illuminate by means of the cursor the selected part element;
(e) screening-off unwanted light from part elements adjacent the
selected part element;
(f) detecting light from the selected part element;
(g) producing signals indicative of predetermined characteristics
of the detected light;
(h) storing representations of the signals;
(i) repeating selected ones of steps (a)-(h) a desired number of
times; and
(j) analyzing the representations of the signals to produce
measurements of the specimen representative of at least one
3-dimensional characteristic of at least a portion of the specimen.
.Iaddend. .Iadd.
11. The method of claim 10 wherein the measurements produced in
step (j) are volumetric measurements. .Iaddend. .Iadd.12. The
method of claim 10 wherein the measurements produced in step (j)
are surface area measurements. .Iaddend. .Iadd.13. The method of
claim 10 wherein the measurements produced in step (j) are light
intensity measurements.
.Iaddend. .Iadd.14. The method of claim 10 wherein the measurements
produced in step (j) are distance measurements. .Iaddend. .Iadd.15.
The method of claim 10 wherein the measurements produced in step
(j) are angular measurements. .Iaddend. .Iadd.16. The method of
claim 10 wherein the measurements produced in step (j) are surface
parameter measurements.
.Iaddend. .Iadd.17. A method for microphotometering a 3-dimensional
specimen using a light detection apparatus, the specimen defining a
plurality of layers, each layer defining a plurality of part
elements, and the detection apparatus defining a focal plane, the
method comprising the following steps:
(a) generating a cursor of light in the focal plane;
(b) positioning at least one of (1) the focal plane and (2) the
specimen such that a desired one of the layers lies in the focal
plane;
(c) selecting at least one of the part elements in the selected
layer;
(d) positioning at least one of (1) the cursor and (2) the specimen
to illuminate by means of the cursor the selected part element;
(e) screening-off unwanted light from part elements adjacent the
selected part element;
(f) detecting light from the selected part element;
(g) producing signals indicative of predetermined characteristics
of the detected light;
(h) storing representations of the signals;
(j) repeating selected ones of steps (a)-(h) a desired number of
times; and
(j) analyzing the representations of the signals to produce a
projected representation from a desired angle of at least a portion
of the specimen.
.Iaddend. .Iadd.18. The method of claim 17 wherein the projected
representation is a 2-dimensional representation of a portion of
the specimen bordered by arbitrarily oriented parallel virtual
planes. .Iaddend. .Iadd.19. The method of claim 17 wherein the
projected representation is a 2-dimensional representation of a
portion of the specimen bordered by arbitrarily oriented
nonparallel virtual planes. .Iaddend. .Iadd.20. An apparatus for
microphotometering a 3-dimensional specimen, the specimen defining
a plurality of layers, each layer defining a plurality of part
elements, the apparatus comprising:
means for detecting light from a focal plane;
means for generating a cursor of light in the focal plane;
means for positioning at least one of (1) the focal plane and (2)
the specimen such that a desired one of the layers lies in the
focal plane;
means for positioning at least one of (1) the cursor and (2) the
specimen to illuminate by means of the cursor a selected part
element;
means fore preventing unwanted light from part elements adjacent
the selected part element from being detected by the means for
detecting light;
means for producing signals indicative of predetermined
characteristics of the detected light;
means for storing representations of the signals; and
means for analyzing the representations of the signals to produce
measurements of the specimen representative of at least one
3-dimensional
characteristic of at least a portion of the specimen. .Iaddend.
.Iadd.21. An apparatus for microphotometering a 3-dimensional
specimen, the specimen defining a plurality of layers, each layer
defining a plurality of part elements, the apparatus
comprising:
means for detecting light from a focal plane;
means for generating a cursor of light in the focal plane;
means for positioning at least one of (1) the focal plane and (2)
the specimen such that a desired one of the layers lies in the
focal plane;
means for positioning at least one of (1) the cursor and (2) the
specimen to illuminate by means of the cursor a selected part
element;
means for preventing unwanted light from part elements adjacent the
selected part element from being detected by the means for
detecting light;
means for producing signals indicative of predetermined
characteristics of the detected light;
means for storing representations of the signals; and
means for analyzing the representations of the signals to produce a
projected representation from a desired angle of at least a portion
of the specimen. .Iaddend.
Description
TECHNICAL FIELD
The invention relates to a method for microphotographing prepared
specimens and displaying the resultant images thereof, by
generating with the aid of a convergent light beam a luminous dot
or cursor in the focal plane of a microscope, matching the cursor
with a plurality of part elements in the prepared specimen,
collecting the light created by the cursor and the prepared
specimen, detecting the collected light, and generating
corresponding electric signals. The invention also relates to
apparatus for carrying out the method.
BACKGROUND ART
Qualitative and quantitative microscopic investigations (study
assays) of prepared specimens of the human body and of animals
constitute an important and time-consuming part of research work,
for example, within the field of medicine. For example, when
wishing to make a close study of a liver there is first prepared a
given number of thin specimens of the liver to be examined (these
specimens being prepared with the aid of a microtome), whereafter
the specimens are subjected to a qualitative and quantitative
examination under a microscope. A picture of the general condition
of the liver, changes in its state of disease, etc., can then be
obtained by combining the results of the assays.
It is also known to obtain the assay result from a plurality of
locations on the surface of a microscope specimen with the aid of
electronic scanning techniques.
When applying known techniques it is still necessary in general to
prepare a relatively large number of specimens (sections) from the
subject to be examined, which is expensive, time-consuming and
highly laborious. The object of the present invention is to
simplify and, in many instances, even to refine the methodology of
effecting such microscopic investigations, and at less cost.
SUMMARY OF THE INVENTION
The method according to the invention comprises producing a
three-dimensional image of a volume of a microscope specimen (i.e.
a specimen for microscopic study) taking a starting point from the
method described in the introduction, and is mainly characterized
by changing the mutual relative positions of the specimen and the
focal plane and renewed matching of the cursor or luminous dot with
a plurality of part elements in the specimen; collecting light
created by the cursor and part elements in the specimen; and
screening-off any synchronous disturbing light created by adjacent
(above, beneath, beside) part elements in the specimen; detecting
the light thus collected and storing the measurement values
resulting from said detection, the storage of the measurement
values being effected synchronously with the matching of the cursor
with the part elements in the specimen and the change in the
relative mutual positions of the specimen and the focal plane, the
measurement values being representative of locations in various
layers through the specimen; and collecting the measurement values
derived from locations in a plurality of layers representative of a
given volume of the specimen in dependence upon upon
planned/desired analysis of the specimen.
The aforesaid measurement values together give a detailed
description or picture of the whole of the volume determined
through all of said plurality of locations. By converting the
measurement values to digital form and storing the same in the
memory of a data processor, it is possible to produce
three-dimensional images suitable for assay and further
analysis.
Thus, it is possible--without preparing fresh physical
specimens--to study the specimen on a data screen from different
projections and to combine two such projections to obtain a
stereoscopic image. This enables the person carrying out the
investigation to produce in a very short time precisely those views
and incident angles which may be desired as the investigation
proceeds.
The study of nerve cells is an example of an area in which the
method according to the invention is particularly well suited.
Nerve cells exhibit an extremely large number of branches and
present a complicated three-dimensional structure. Investigatory
studies of such structures with the aid of traditional microscope
equipment are extremely difficult to carry out and are also very
time-consuming. In addition the information obtained therefrom is
incomplete. Corresponding studies carried out in accordance with
the invention have been found to provide abundantly more
information than that obtained when carrying out the studies in
accordance with known methods. Other possible areas where the
three-dimensional structure is of great interest include studies of
the inner structures of cells, for example a study of the
configuration of the cell core, chromosomes etc.
The illumination and registration technique according to the
invention affords the following advantages. It is possible to
select a thin section from the specimen for registration and to
combine several such sections to produce a three-dimensional image.
The images are made richer in contrast and clearer by decreasing
the level of stray light. Sensitive and delicate specimens are
protected from harm, because the total light exposure is low .
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will now be described in more detail with reference
to the accompanying schematic drawings, in which
FIG. 1 illustrates in perspective the contour of a specimen and a
section laid through the specimen;
FIG. 2 is a vertical sectional view of a specimen with a section
according to FIG. 1 laid in the surface structure of the
specimen;
FIG. 3 illustrates apparatus for microphotometering a microscope
specimen while using reflected and/or fluorescent light, comprising
a two-dimensional scanner and a vertically movable object
table;
FIG. 4 illustrates the apparatus according to FIG. 3 modified with
a single-dimension scanner and a vertically and laterally
adjustable table;
FIG. 5 illustrates the apparatus according to FIG. 3 which lacks
the scanner but has an object table which can be moved in three
dimensions;
FIG. 6 illustrates the apparatus according to FIG. 5 modified for
transmitted or fluorescent light; and
FIG. 7 illustrates a specimen in which a plurality of sections have
been laid.
DETAILED DESCRIPTIONS OF THE PREFERRED EMBODIMENTS
In FIG. 1 the reference 10 identifies a microscope specimen through
which there is laid an imaginary horizontal section comprising a
plurality of part elements: for reasons relating to the
technicalities of the drawing the section exhibits 20 rows in the
x-direction and 15 rows in the y-direction, i.e. a total of 300
part elements, such as part elements 12 and 13 for example, but may
in practice of course exhibit many more or far less elements and
with sections of a different form, such as square or elongated
rectangular sections for example, depending entirely upon the form
of the specimen.
When microphotometering a microscope specimen, 75, 100 or may be
200 such imaginary sections may be envisaged in practice, these
sections being plane parallel and bordering upon one another, two
and two, or spaced equidistantly from one another. That part of the
section 11 which lies within the specimen 10 has been shown in the
figure with a thicker line 14.
The specimen 20 illustrated in vertical sections in FIG. 2
constitutes part of a material surface to be studied. A section 21,
corresponding to the section 11 in FIG. 1, is placed in the upper
part of the specimen and is thus here seen from the side. The two
indicated sections 11 and 21 are representative of what is referred
to hereinafter as "the focal plane".
The apparatus illustrated in FIG. 3 includes a microscope 30 having
an object table 301, a laser-light source 31 for producing a beam
of light through a beam-splitting unit 32, and a scanner 33
operative in panning the beam of light to a plurality of locations
in the focal plane (x-y-plane) of the microscope 30, an aperture
34, and a control and data-collection assembly 36 for controlling,
inter alia, the scanner 33 via a line 361, and for collecting
electric signals deriving from reflected and/or fluorescent light
arriving at the detector 35 after having passed from the object
table 301 through the microscope 30, the scanner 33 and the
aperture 34, this light being converted in the detector 35 to
electric signals which are transferred through the line 351 to the
control assembly 36, and finally externally located equipment for
storing, processing and visually displaying data originating from
said signals, this equipment comprising a data processor 37 and an
auxiliary store 38, and a display screen 39 connected to the data
processor 37.
A luminous dot or cursor created by the light beam from the laser
source 31 is deflected by the scanner 33 to a number of positions
in a specimen placed on the object table 301, in the focal plane,
which focal plane may be the section indicated in FIG. 1. Stray
light, possibly eminating from locations (volume elements) above,
beneath or beside the location in the x-y-plane just scanned by the
scanner 33, is excluded by the aperture 34 and is caused to deliver
information relating to its characteristics through, for example,
reflected light. When a location has been scanned a control pulse
is delivered from the control assembly 36 to the scanner 33, via
the line 361, and the scanner therewith reflects the beam to the
next location (e.g. an x-square) in the same row (y-row), this
procedure being continued until the whole of section 11 has been
scanned or sensed. The object table 301 is thereupon moved stepwise
(up or down) in response to a control pulse (signal) fed from the
control assembly 36 to a drive unit 363 via the line 362, which
drive unit guides directly movement of the table 301 is the
z-direction. The object table with the specimen thereon is thus
displaced through a given distance in the z-direction, whereupon
the focal plane of the microscope 30 will obtain a new position
through the specimen, this new position being scanned in the same
manner as that previously described. The whole of the specimen is
thus scanned in this way successively at equidistant locations
along equidistant parallel lines in equidistant planes. Signals are
transferred from the scanner 33 and the drive unit 363 respectively
to the controller assembly 36, bearing information relating to the
current position of the cursor created by the light beam
(x-y-direction) and of the table 301 (z-direction).
When creating a three-dimensional picture of a volume of a
microscope specimen with the aid of the apparatus just described,
the following operational steps are taken:
a luminous dot or cursor is created in the focal plane 11 of the
microscope 30, this plane passing through the specimen;
the cursor is deflected to a plurality of locations in the focal
plane 11;
the mutual relative positions of the specimen and the focal plane
11 are changed and deflection of the cursor to a plurality of
locations in the focal plane is renewed;
the change in the relative mutual positions of the specimen and
focal plane is repeated stepwise, and after each such change the
luminous cursor is again deflected to a number of locations in the
focal plane;
the light created by the luminous cursor and part elements of the
specimen is collected, this light carrying information relating to
locations in the specimen, and any disturbing light eminating
synchronously from adjacent locations is screened-off; and
the thus collected light is collected and the measurement values
obtained through said detection are stored, the storage of the
measurement values being effected synchronously with the deflection
of the luminous cursor in the focal plane and with the change in
the mutual position between the specimen and the focal plane.
In this way there is obtained a description or picture of the whole
of the volume of the specimen comprising the individual volume
elements (the locations), this being achieved in an extremely short
period of time. By way of example it can be mentioned that when
microphotometering a specimen through approximately 100 sections
and having 256.sup.2 measurement values (locations) in each
section, the actual apparatus time is approximately 10 minutes. In
addition to the highly simplified preparation of the specimen,
however, it is also possible to produce through the data processor
37 three-dimensional images with selectable projection directions
and with the possibility of making volumetric measurements.
The apparatus illustrated in FIG. 4 coincides with the apparatus
illustrated in FIG. 3 with the exception that deflection caused
through the scanner 43 is effected only in one direction (e.g. the
y-direction), while the object table 401 is moved stepwise in the
horizontal direction (x-direction) subsequent to the light beam
having been advanced along a whole row or line and been displaced
stepwise in a vertical direction (z-direction) subsequent to the
light beam having been advanced along a whole section. This
modification may be suitable when studying specimens of
substantially elongated rectangular shape.
When the aforegiven exceptions in the functioning of the apparatus,
the corresponding circuits and devices illustrated in FIGS. 3 and 4
are identified by reference numerals differing only in their first
digits.
The apparatus illustrated in FIG. 5 coincides with that illustrated
in FIG. 3 with the exception that the scanner 33 is omitted totally
and the object table 501 is instead arranged to be moved stepwise
along a surface in the horizontal plane (x-y-plane) and stepwise in
a vertical direction (z-direction). These movements are controlled
from the drive unit 563 which receives, in turn, synchronizing
pulses from the control assembly 56.
Mutually corresponding circuits and devices in FIGS. 3 and 5 are
identified by reference numerals differing only in their first
digits.
The apparatus according to FIGS. 3-5 are intended to utilize
reflected and/or fluorescent light from the specimen. It is also
possible to work with transmitted light, however, and the apparatus
illustrated in FIG. 6 is intended for this case. Light from the
laser 61 passes the microscope 60 and is focused on a point in the
focal plane in a specimen placed on the object table 601. The light
allowed to pass through or excited (fluorescence) by the specimen
at the point in question is collected by an objective 602 and
permitted to pass an aperture 64 and, in the case of fluorescence,
a filter 603 to eliminate exiting laser light, whereupon detection
is effected in the detector 65 (conversion to electric signals and
analogue/digital conversion) and collection in the control and data
collecting assembly 66 in the aforedescribed manner. In a manner
similar to that described with reference to FIG. 5, the object
table 601 is also caused to move stepwise, in response to control
signals from the assembly 66, along a line or row in a surface
plane (x-y-plane) and in a direction (z-direction) perpendicular to
the surface plane. The function of the apparatus is similar in
other respects to the function of the previously described
apparatus.
The various remaining circuits or devices in FIG. 6 corresponding
to the circuits or devices in FIG. 5 are identified by reference
numerals differing only in their first digits.
The invention is not restricted to the aforedescribed and
illustrated embodiments. For example, although the methods forming
the basis for the apparatus illustrated in FIGS. 3 and 4, see also
the following claims 2 and 3, probably give optimal results in
respect of reflected light, modifications can be made in principle
for the use of transmitted light. In addition, the drive units 363,
463 and 563 of respective apparatus according to FIGS. 3--5 can
also be used to advantage for controlling movement of the
microscope objective in z-directions instead of respective object
tables 301, 401 and 501. There is obtained in both instances (fixed
objective, movable object table in z-direction; movable objective
in z-directions, fixed object table in z-directions) a change in
the mutual distance between the specimen 10 and the focal plane
11.
In the aforegoing mention has been made as to how the light beam is
stepped forward along a line on (in) the specimen with the aid of
control signals from the control assembly (e.g. 36 in FIG. 3).
Modifications may be made, however, to enable the light beam to be
swung continuously forwards and backwards for example, but so that
detection of the reflected signal takes place exactly at moments in
time corresponding to given positional locations in the focal plane
in the specimen.
It has been mentioned in the aforegoing that images in selectable
projections can be readily obtained once the specimen has been
microphotometered in accordance with the invention.
FIG. 7 illustrates schematically a specimen 10 through which
sections 1-n have been laid (at right angles to the plane of the
drawing) in accordance with the invention. A researcher who during
the course of his/her work finds that he needs to view a section
through a given part of the specimen from a different angle, e.g.
through sections 70--70, is able to immediately obtain from the
measurement value equipment an image comprised of measuring results
from a plurality of sections 1-n, and with a starting point from
this view image can then find reason to concentrate his/her
interest to another part of the specimen, perhaps along an
additional section. The possibilities are manifold and afford a
high degree of flexibility in respect of research work.
* * * * *