GB2034913A

GB2034913A - Microscope stage

Info

Publication number: GB2034913A
Application number: GB7845390A
Authority: GB
Original assignee: Coal Industry Patents Ltd
Current assignee: Coal Industry Patents Ltd
Priority date: 1978-11-21
Filing date: 1978-11-21
Publication date: 1980-06-11

Abstract

A mechanical stage for incident light microscopy has a body portion, 1, and a base plate, 2, movable in X-and Y-axes with respect to the body portion, the base plate having slide location abutments, 8, and at least two slide biasing members, 10, whereby a slide may be positioned in edge contact with the location abutments and the biasing members maintain the slide parallel to the base plate, and prevent it tilting with respect to the base. <IMAGE>

Description

SPECIFICATION Microscope stage This invention concerns optical microscope stages, more especially it concerns microscope stages for incident light microscopy.

Microscopy is mainly concerned with trans mitted light, and microscope manufacturers concentrate on making transmitted light accessories. Such accessories include the socalled "mechanical stages" which permit a slide mounted sample to be moved under the microscope to allow analysis of varying areas of the sample. It is known to have a mechanical stage comprising an L-shaped slide holder having a spring-loaded arm which bears against a corner of the slide and urges it into accurate location within the L. The slide holder can be moved in the X-and Y-axes by accurate mechanical adjustment means which are part of an L-shaped body portion.This mechanical stage is normally mounted on a rotating stage, which comprises a rotatable table fitted under the microscope objective, by the provision of two pins on the underside of the body portion which locate in holes in the rotatable table, and a screw extending through the body portion and engaging a threaded hole in the rotatable table. The slide holder and the body portion are provided with vernier scales to accurately record the position of the slide during analysis. The slide is placed on the rotatable table, positioned against the internal edges of the L shaped slide holder then the spring-loaded arm biases the slide into accurate position.

It has been found, however, that the use of a spring-loaded arm contacting the corner of the glass slide tends to lift that corner, so that the slide is not parallel to the rotatable plate, and moreover, that individual slides are tilted to different degrees according to their thickness. The tilting of the slide does not cause problems with transmitted light microscopy.

In incident light microscopy, in which the light is reflected off the surface of the sample, the slightest amount of tilting is unacceptable as the reflected light can partially or even completely miss the objective.

It is not believed that an incident light mechanical stage has been marketed. The present inventors aimed to design a simple yet effective incident light mechanical stage.

The present invention provides an incident light mechanical stage for optical microscopy comprising a body portion and a base plate movable in X-and Y-axes with respect to said body portion, said base plate having slide location abutments and at least two slide biasing members whereby a slide may be positioned in edge contact with said location abutments and the biasing members maintain the slide parallel to said base plate.

The invention will now be described with reference to the accompanying drawing, which is a perspective view of a mechanical stage according to the invention, with a plain slide mounted thereon.

The stage has an L-shaped body portion 1; a metal base plate, 2, the upper and lower surfaces of which are flat and parallel to one another, is fixed to position adjustment rack and pinion mechanisms (not shown) mounted on the underside of body portion 1. Such mechanisms are well known in the art, and other position adjustment mechanisms may be used. The base plate 2 may be moved in the X-and Y-directions by movement of the rotatable knobs 3a and 3b, and vernier scales 4 and 5 to identify positions on the X and Y-axes; vernier scale 5 is on a block 6 sliding in slot 7, the block moving together with the Y-axis control knob 3b.

Firmly and accurately mounted in the base plate are three hard metal pins 8 which act as slide location abutments. Also mounted in the base plate are studs 9, each carrying a short coil spring 10 which act as slide biasing members. A plain glass slide is shown in position on the stage. Location of the slide is straightforward and is accomplished by slipping the slide under the coil springs 10 and against the pins 8. Surprisingly, this arrangement gives consistent location of the slide as well as ensuring that the surface of the slide, or more correctly the surface of a sample thereon, is parallel to the base plate.

The underside of the body portion 1 has raised portions 11 and location pins, not shown, to permit the stage to be mounted on a rotatable stage or the like and to allow the base plate to move in contact with and parallel to the surface of the rotatable stage.

In place of the coil springs, other biasing members, such as leaf springs, may be used, although it is thought that the coil springs offer the easiest insertion of the slide because of their shape and also are not affected by different slide thicknesses.

Another embodiment of the present invention has a hole or slot in the base plate which allows a single stage to be used without modification for incident and transmitted light microscopy.

Other variations of the embodiment illustrated will be clear to those skilled in the art without departing from the scope of the invention. For example, in another embodiment, the invention can also be used on the known rectagular object stage which has a built-in or attachable mechanical stage with graduation and verniers.

1. An incident light mechanical stage for optical microscopy comprising a body portion and a base plate movable in X-and Y-axes with respect to said body portion, said base plate having slide location abutments and at

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Microscope stage This invention concerns optical microscope stages, more especially it concerns microscope stages for incident light microscopy. Microscopy is mainly concerned with trans mitted light, and microscope manufacturers concentrate on making transmitted light accessories. Such accessories include the socalled "mechanical stages" which permit a slide mounted sample to be moved under the microscope to allow analysis of varying areas of the sample. It is known to have a mechanical stage comprising an L-shaped slide holder having a spring-loaded arm which bears against a corner of the slide and urges it into accurate location within the L. The slide holder can be moved in the X-and Y-axes by accurate mechanical adjustment means which are part of an L-shaped body portion.This mechanical stage is normally mounted on a rotating stage, which comprises a rotatable table fitted under the microscope objective, by the provision of two pins on the underside of the body portion which locate in holes in the rotatable table, and a screw extending through the body portion and engaging a threaded hole in the rotatable table. The slide holder and the body portion are provided with vernier scales to accurately record the position of the slide during analysis. The slide is placed on the rotatable table, positioned against the internal edges of the L shaped slide holder then the spring-loaded arm biases the slide into accurate position. It has been found, however, that the use of a spring-loaded arm contacting the corner of the glass slide tends to lift that corner, so that the slide is not parallel to the rotatable plate, and moreover, that individual slides are tilted to different degrees according to their thickness. The tilting of the slide does not cause problems with transmitted light microscopy. In incident light microscopy, in which the light is reflected off the surface of the sample, the slightest amount of tilting is unacceptable as the reflected light can partially or even completely miss the objective. It is not believed that an incident light mechanical stage has been marketed. The present inventors aimed to design a simple yet effective incident light mechanical stage. The present invention provides an incident light mechanical stage for optical microscopy comprising a body portion and a base plate movable in X-and Y-axes with respect to said body portion, said base plate having slide location abutments and at least two slide biasing members whereby a slide may be positioned in edge contact with said location abutments and the biasing members maintain the slide parallel to said base plate. The invention will now be described with reference to the accompanying drawing, which is a perspective view of a mechanical stage according to the invention, with a plain slide mounted thereon. The stage has an L-shaped body portion 1; a metal base plate, 2, the upper and lower surfaces of which are flat and parallel to one another, is fixed to position adjustment rack and pinion mechanisms (not shown) mounted on the underside of body portion 1. Such mechanisms are well known in the art, and other position adjustment mechanisms may be used. The base plate 2 may be moved in the X-and Y-directions by movement of the rotatable knobs 3a and 3b, and vernier scales 4 and 5 to identify positions on the X and Y-axes; vernier scale 5 is on a block 6 sliding in slot 7, the block moving together with the Y-axis control knob 3b. Firmly and accurately mounted in the base plate are three hard metal pins 8 which act as slide location abutments. Also mounted in the base plate are studs 9, each carrying a short coil spring 10 which act as slide biasing members. A plain glass slide is shown in position on the stage. Location of the slide is straightforward and is accomplished by slipping the slide under the coil springs 10 and against the pins 8. Surprisingly, this arrangement gives consistent location of the slide as well as ensuring that the surface of the slide, or more correctly the surface of a sample thereon, is parallel to the base plate. The underside of the body portion 1 has raised portions 11 and location pins, not shown, to permit the stage to be mounted on a rotatable stage or the like and to allow the base plate to move in contact with and parallel to the surface of the rotatable stage. In place of the coil springs, other biasing members, such as leaf springs, may be used, although it is thought that the coil springs offer the easiest insertion of the slide because of their shape and also are not affected by different slide thicknesses. Another embodiment of the present invention has a hole or slot in the base plate which allows a single stage to be used without modification for incident and transmitted light microscopy. Other variations of the embodiment illustrated will be clear to those skilled in the art without departing from the scope of the invention. For example, in another embodiment, the invention can also be used on the known rectagular object stage which has a built-in or attachable mechanical stage with graduation and verniers. CLAIMS

1. An incident light mechanical stage for optical microscopy comprising a body portion and a base plate movable in X-and Y-axes with respect to said body portion, said base plate having slide location abutments and at least two slide biasing members whereby a slide may be positioned in edge contact with said location abutments and the biasing members maintain the slide parallel to said base plate.

2. A stage according to claim 1, wherein there are at least three slide location abutments.

3. A stage according to claim 2, wherein the slide location abutments comprise pins mounted at right angles to the base plate.

4. A stage according to claim 1, 2 or 3, wherein the biasing members are coil springs mounted with their axes parallel to the base plate.

5. A stage according to any one of claims 1 to 4, wherein the base plate is moved relative to the body portion by rack and pinion mechanisms.

6. A stage according to any one of the preceding claims, wherein the base plate has a hole or slot to permit transmitted light microscopy.

7. A stage according to claim 1, substantially as hereinbefore described.