Abstract: A holographic interferometry apparatus for inspecting cylindrical optical surfaces. Laser light is split into regular reflection light and diffraction light by a holographic optical element. A reference reflector plate receives the regular reflection light. An object with a cylindrical optical surface receives the diffraction light. The object is held on a specimen holder table which has a four-axis adjustment mechanism which allows adjustments in the X,Y,Z and .theta. directions. Interference fringes are formed by the interference of light reflected from the object and from the reflector plate.

Abstract: Disclosed herein is an interferometric surface inspection machine which is arranged to facilitate the inspection of finished spherical lens surfaces, and which essentially includes: a surface plate formed with a through light guide opening in a predetermined position; an up-down guide means suspended from the lower side of the surface plate; an interferometer liftably supported on the up-down guide means and having a reference lens with a reference surface thereof disposed on the side of the light guide opening and in face to face relation with said light guide opening; and a lens mount portion adjustably located in a predetermined position above the light guide opening in the surface plate and adapted to support peripheral edge portions of a spherical lens element on the side of the lens surface to be inspected.

Abstract: A subject position adjusting apparatus for use with an interferometer has a leveling stand disposed on a stationary stand of the interferometer. A leveling standard is stationary relative to and extends upright from the leveling stand. The leveling standard carries a subject stage for up and down movement in an axial direction of a light beam. A leveling mechanism is disposed between the stationary stand and the leveling stand. The leveling mechanism controls the angle of the leveling stand relative to a horizontal plane so as to level the leveling standard and make it parallel to the axial direction.

Abstract: A laser interferometer for inspecting the surface condition of a specimen by irradiating the specimen on a specimen support mechanism with a laser beam projected thereto through a reference plate, and observing the interference fringe produced by interference between reflected light from a reference surface of the reference plate and a surface of the specimen under inspection, the laser interferometer includes: an interferometer housing accommodating therein an optical laser beam guide member and an optical interference fringe imaging member, and is provided with a laser beam guide portion in a wall portion thereof; a laser tube mount member of a cylindrical form projected on the outer side of the housing and positioned in such a manner so as to circumvent the laser guide portion; and a laser tube detachably fitted in the laser tube mount member.