Microscope

1. A microscope comprising:

a main body that has a substantially C-shape in side view, and that comprises a lower horizontal portion, an upper horizontal portion, and a brace portion, the brace portion connecting between the lower horizontal portion and the upper horizontal portion at respective rear sides thereof;

a transmitted light source;

a collector lens that transforms the illumination light from the transmitted light source into substantially parallel light; and

a transmitted-light illumination optical system that brings illumination light from the transmitted light source to a specimen supported by the main body, and illuminates the specimen with the illumination light transmitted therethrough,

wherein the lower horizontal portion and the brace portion are integrated to form an L-shape frame,

wherein the transmitted-light illumination optical system and the transmitted light source are removably attachable to the frame of the main body,

wherein the transmitted-light illumination optical system includes:

a field stop that restricts the illumination light transmitted through the collector lens;

a mirror that deflects an optical path of the illumination light passing through the field stop; and

a window lens that projects a field stop image from the mirror on substantially infinity,

wherein at least the transmitted light source and the collector lens are removably attachable to a rear side of the frame in an integrated manner, and

wherein at least the field stop, the mirror, and the window lens are removably attachable to a front side of the frame in an integrated manner.

2. The microscope according to claim 1 , wherein at least one of the transmitted-light illumination optical system and the transmitted light source can be selected from among multiple types of transmitted-light illumination optical systems and transmitted light sources, and

wherein the frame is configured to removably mount thereon the transmitted-light illumination optical system and the transmitted light source interchangeably.

3. The microscope according to claim 2 , wherein the transmitted-light illumination optical system can be selected from a first transmitted-light illumination optical system and a second transmitted-light illumination optical system, the first transmitted-light illumination optical system including at least one of a color conversion filter and a neutral density filter, and the second transmitted-light illumination optical system including no color conversion filter and no neutral density filter, and

wherein the first transmitted-light illumination optical system and the second transmitted-light illumination optical system are interchangeably removably attachable to the frame.

4. The microscope according to claim 2 , wherein the transmitted light source can be selected from a halogen light source and a light-emitting diode light source, and

the halogen light source and the light-emitting diode light source are interchangeably removably attachable to the frame.

5. The microscope according to claim 1 , wherein the transmitted-light illumination optical system further includes a color conversion filter and a neutral density filter, and

wherein the field stop, the mirror, the window lens, and at least one of the color conversion filter and the neutral density filter are removably attachable to the front side of the frame in an integrated manner.

6. The microscope according to claim 1 , further comprising a condenser lens that brings the illumination light from the transmitted light source to the specimen, and includes a first lens group, an aperture stop, and a second lens group,

wherein the first lens group is contained in the transmitted-light illumination optical system that is removably attachable to the front side of the frame in the integrated manner.

7. The microscope according to claim 1 , further comprising a power source which powers the transmitted light source, the power source being removably attachable to the main body.