U.S. patent application number 10/446215 was filed with the patent office on 2003-11-06 for microscope, especially laser scanning microscope.
Invention is credited to Simon, Ulrich, Stock, Michael, Wolleschensky, Ralf.
Application Number | 20030206341 10/446215 |
Document ID | / |
Family ID | 28676188 |
Filed Date | 2003-11-06 |
United States Patent
Application |
20030206341 |
Kind Code |
A1 |
Wolleschensky, Ralf ; et
al. |
November 6, 2003 |
Microscope, especially laser scanning microscope
Abstract
A microscope, especially a laser scanning microscope, with
illumination over one wavelength and/or a plurality of wavelengths,
wherein a controlling of the intensity of at least one wavelength
is carried out by at least one rotatable interference filter which
is arranged in the illumination beam path, wherein the at least one
wavelength is at least partially reflected out of the illumination
beam path and a plurality of filters for different wavelengths can
be arranged one behind the other in the illumination beam path.
Inventors: |
Wolleschensky, Ralf;
(Schoeten, DE) ; Simon, Ulrich; (Rothenstein,
DE) ; Stock, Michael; (Apolda, DE) |
Correspondence
Address: |
REED SMITH, LLP
ATTN: PATENT RECORDS DEPARTMENT
599 LEXINGTON AVENUE, 29TH FLOOR
NEW YORK
NY
10022-7650
US
|
Family ID: |
28676188 |
Appl. No.: |
10/446215 |
Filed: |
May 27, 2003 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
10446215 |
May 27, 2003 |
|
|
|
09366883 |
Aug 4, 1999 |
|
|
|
6594074 |
|
|
|
|
Current U.S.
Class: |
359/385 ;
359/368; 359/381; 359/885 |
Current CPC
Class: |
G02B 21/002 20130101;
G02B 21/06 20130101 |
Class at
Publication: |
359/385 ;
359/368; 359/381; 359/885 |
International
Class: |
G02B 021/00; G02B
021/06; G02B 005/22 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 4, 1998 |
DE |
198 35 068.6 |
Claims
What is claimed is:
1. A microscope, especially a laser scanning microscope,
comprising: means for providing illumination over at least one of a
single wavelength and a plurality of wavelengths; and means for
controlling the intensity of at least one wavelength being carried
out by at least one rotatable interference filter which is arranged
in an illumination beam path, said at least one wavelength being at
least partially reflected out of the illumination beam path.
2. The microscope according to claim 1, wherein a plurality of
filters for different wavelengths are arranged one behind the other
in the illumination beam path.
3. The microscope according to claim 1, wherein pairs of filters
with identical wavelength characteristics are provided for at least
one wavelength for compensating the beam offset.
4. The microscope according to claim 1, wherein at least one filter
is traversed twice in that a reflector returns the illumination
light via the filter.
Description
BACKGROUND OF THE INVENTION cl a) FIELD OF THE INVENTION
[0001] The invention relates to laser scanning microscopes and, in
particular, an improvement in such microscopes for controlling the
intensity of one wavelength of illumination.
OBJECT AND SUMMARY OF THE INVENTION
[0002] The primary object of the invention is to provide an
improvement in laser scanning microscopes where the intensity of
one wavelength of illumination is controlled.
[0003] In accordance with the invention, a microscope, especially a
laser scanning microscope, comprises means for providing
illumination over at least one of a single wavelength and a
plurality of wavelengths and means for controlling the intensity of
at least one wavelength being carried out by at least one rotatable
interference filter which is arranged in an illumination beam path.
The at least one wavelength is at least partially reflected out of
the illumination beam path.
BRIEF DESCRIPTION OF THE DRAWINGS
[0004] In the drawings:
[0005] FIG. 1 illustrates a microscope unit and scan head of a
laser scanning microscope;
[0006] FIGS. 2a and 2b illustrate rotation of dichroics for
influencing the wavelengths in accordance with the invention;
and
[0007] FIG. 3 illustrates in schematic and pictorial the effect of
the invention on chosen wavelengths.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0008] A microscope unit M and a scan head S connected thereto are
shown schematically in FIG. 1.
[0009] A light source LQ1 with illumination optics illuminating the
object on the microscope stage T via a beam splitter ST1 in a
conventional manner is provided in the microscope.
[0010] A swivelable mirror S3 serves to switch to transmitted-light
illumination by means of a light source LQ2 via the condensor
KO.
[0011] Observation through an eyepiece OK is carried out via a tube
lens TL and a mirror S1. In addition, by means of this mirror or
beam splitter S1, the scanning beam path is coupled in via the
scanning lens SL and the scanner SC.
[0012] The light of a laser module LM is coupled in in the
direction of the scanner SC via light conductor F, collimating
optics KO, mirror S2 and beam splitter ST2.
[0013] The light coming from the object travels through the scanner
SC and dichroic beam splitter ST2 in the direction of detection,
represented herein by way of example by another beam splitter ST3
for splitting into detection beam paths with pinholes PH1, 2,
filters Fl1, 2 and detectors DT1, 2.
[0014] A plurality of lasers L1, L2, L3 with different wavelengths
are provided in the laser module; these lasers L1, L2, L3 can also
be multiline lasers. They are combined via mirrors and beam
splitter S4, respectively, and coupled into a coupling-in unit FC
in the light conductor F.
[0015] Before being coupled in, they pass a mirror S5 and a filter
unit FE, as is shown in FIG. 2b, and are deflected, again via a
filter unit FE, in the direction of the coupling-in unit by a
reflector R.
[0016] Dichroics DC1, 2, 3, 4, 5, 6 which have a
wavelength-dependent and angle-dependent reflectivity are arranged
in the filter unit FE. This is shown by way of example in FIG. 3
with reference to the angle-dependent reflectivity for the three
wavelengths in which the mirror coating is optimized for 45
degrees, i.e., the greatest reflectivity for a determined
wavelength occurs at 45 degrees. Therefore, the transmission is
adjusted in a continuous manner for the respective wavelength by
rotation. The rest of the wavelengths are not affected.
[0017] The optimization at 45 degrees is given by way of example;
other angles could also be selected for the greatest
reflectivity.
[0018] The light component that is reflected out is suppressed in a
suitable manner, for example, by light traps. Since the rotation of
the dichroics generates a beam offset, these dichroics are arranged
in pairs for compensation.
[0019] In FIGS. 2a and 3, pairs of dichroics DC1, 2 for a
wavelength .lambda.1, DC3, 4 for a wavelength .lambda.2, and DC5, 6
for a wavelength .lambda.3 are arranged in a continuous beam path
so as to be selectively reflecting and can accordingly influence
these wavelengths and compensate the beam offset by means of the
paired arrangement.
[0020] FIG. 2b shows another arrangement as in FIG. 1, wherein the
beam offset is compensated by passing twice through the dichroics
DC1, DC3, DC5 for the three wavelengths.
[0021] The driving means for the rotation of the dichroics are
carried out in a manner familiar to the person skilled in the art,
in this case, as is shown schematically in FIGS. 2a and b, by
toothed wheels to which the dichroics are fastened, wherein the
toothed wheels of the pairs of dichroics in FIG. 2a mesh with one
another and accordingly ensure a coupled movement of the pairs of
toothed wheels.
[0022] A pinion R which is driven by a motor M is provided for
driving the toothed wheels. The driving of the motors can be
carried out via a central control unit AE which, for example,
controls a predetermined illumination and detection mode which
includes the attenuation/adjustment of determined laser
wavelengths.
[0023] In a multi-wavelength laser, or when a plurality of laser
wavelengths are coupled into a microscope jointly, especially in a
laser scanning microscope, one or more wavelengths can
advantageously be adjusted, i.e., attenuated, continuously with
respect to intensity. If the lasers should be exchangeable, a
plurality of such interchangeable filter units with different
wavelengths can also be provided.
[0024] The dichroics utilized herein are interference filters such
as those supplied, for example, by Laseroptik GmbH, also in pairs
for compensating beam offset. Further, dichroics of the
above-mentioned type can also be used advantageously for
wavelength-dependent influencing of the detection beam path, for
example, in FIG. 1, in a detection beam path following the beam
splitter ST2 for the suppression of especially unwanted
wavelengths, for example, of the excitation wavelength in
fluorescence detection.
[0025] While the foregoing description and drawings represent the
preferred embodiments of the present invention, it will be obvious
to those skilled in the art that various changes and modifications
may be made therein without departing from the true spirit and
scope of the present invention.
* * * * *