Abstract: When an image of a sample is photographed by an image pickup device and it is converted into an electric signal, then the electric signal is converted by a controller into a signal suitable for a display unit, and the image of the sample is displayed on a screen of the display unit. A light flux from the screen of the display unit is guided by an optical system to an observing optical system. The display screen, on which the image of the sample is displayed, can be observed through an eyepiece lens of the observing optical system. Accordingly, it is easy to confirm the relationship between the size of the picture element of the image pickup device and the image to be photographed and the resolving power for the image intended to be photographed. The display unit and the image pickup device are accommodated in a microscope housing. Therefore, the installation area and the size can be made equivalent to those used for the conventional system.

Abstract: A photographing unit for a microscope has a photometric detector to measure brightness of light from a sample and includes a changing member which changes a brightness of light toward an observation system and a control unit which controls the light based on a detection output of the photometric detector. In addition, the changing member can be controlled based on the presence of an observer. A shielding member can be provided that automatically shields an optical path of the observation system. An illumination system for an index on a reticle can be provided so that the illumination of the reticle can be performed or extinguished at desired times. Additionally, the color of light with which the index is illuminated may be made distinguishable from the color of light from a sample, and the contrast of the index to the sample can be controlled.

Abstract: A photographing unit for a microscope has a photometric detector to measure brightness of light from a sample and includes a changing member which changes a brightness of light toward an observation system and a control unit which controls the light based on a detection output of the photometric detector. In addition, the changing member can be controlled based on the presence of an observer. A shielding member can be provided that automatically shields an optical path of the observation system. An illumination system for an index on a reticle can be provided so that the illumination of the reticle can be performed or extinguished at desired times. Additionally, the color of light with which the index is illuminated may be made distinguishable from the color of light from a sample, and the contrast of the index to the sample can be controlled.

Abstract: A focusing glass and photographic system employing the same are disclosed. The photographic system includes an objective lens operable to form a real image of an object. The focusing glass is adapted to be situated at the real-image position, and comprises a semitransparent region surrounding a fully transmissive photographic zone. The photographic zone defines a region of the field of view of the objective (the field of view being viewable on the focusing screen) defining the metes and bounds of a photographic image obtainable using the photographic system.