Patent ID: 7184212

Claim:
An observation apparatus comprising: two projection devices; a display panel; a retaining member for retaining said display panel; and a supporting member for supporting said retaining member and said two projection devices; wherein said two projection devices are each provided with an aperture, and are configured such that images are projected through the apertures onto said display panel; said display panel is provided with an image-forming element having positive optical power, said image-forming element being positioned in the vicinity of said display panel such that conjugate positions of said apertures are formed at pupil positions for observation; and said retaining member is provided with a retaining mechanism, said retaining mechanism being configured such that said display panel is detachably attachable to said supporting member so as to enable a sterilized display panel to be readily provided; said display panel comprises a Fresnel reflective plate that is made of a material that is suitable for reuse after undergoing a sterilization process of autoclaving or gamma ray irradiation, and a diffusive film which is made of a material that is not suitable for reuse after undergoing a sterilization process of autoclaving or gamma ray irradiation; said retaining member is detachable from said supporting member so as to allow the retaining mechanism to be sterilized; and said diffusive film is detachably attached to a surface of said Fresnel reflective plate so that the diffusive film may be removed after sterilization and use.