Abstract: Apparatus is provided for guiding a pellicle-covered photomask or other flat object into viewing position for inspection upon a flat top plate of a stage below the objective of a microscope. The apparatus includes a pair of spaced parallel rails having inwardly extending upper and lower flanges that define opposed keyways in which keybars at the edges of a photomask-carrying paddle slide. To protect the pellicle membrane and to space the latter above the top stage top plate, at entrance ends of the rails, segments of the upper flanges are recessed greater than the width of the paddle to permit a vertical dropping movement of the leading end of paddle onto inlet horizontal guide surfaces. These guide surfaces are broad platforms on which may be deposited the leading end of the paddle.

Abstract: Transparent membranes are examined with a microscope having coaxial brightfield illumination fitted with a narrow bandwidth filter to convert polychromatic light from a source to substantially monochromatic light. Light reflecting off of the surfaces of the membrane recombine to create an interference pattern, including observable fringes in the region of membrane surface aberrations. Membranes which may be examined include pellicles used to cover photomasks and photo-resist layers. If a photo-resist layer is examined, a filter is selected to provide essentially monochromatic light at a wavelength to which the resist is insensitive.

Abstract: An apparatus positions a flat, rectangular object, such as a photomask, on a stage below the objective of a microscope in the XY plane with provision for rotation in the XY plane to correct for a theta shift. A pair of rails are mounted parallel on the stage and may be adjustably mounted to hold different sizes of flat objects therebetween. The members for locating the object in an exact X and Y location on the rails and for theta shifting the object are preferably mounted on the respective rails and are movable therewith to accommodate various sizes of objects. An inexpensive theta shift is achieved by inexpensive stops and pivot mounted on one rail and a spring biased plunger and an adjustable member on the other rail.

Abstract: Embryos and ova are manipulated at a work station that includes a microscope, a stage positioned below the objective the microscope on which an embryo- or ovum-containing sample is placed and micromanipulators and associated tools for operating on or otherwise manipulating the embryo or ovum. The specimen is illuminated with both bright-field illumination and dark-field illumination of contrasting hue to produce a composite image of the embryos or ova with the embryos or ova glowing with the dark-field hue against a bright background. The bright-field is transmitted through an aperture that is narrow to obtain a depth of field that is appropriate to three-dimensional manipulation.

Abstract: Apparatus is provided for attachment to a microscope which alternately positions a filter in alignment with the objective of the microscope and stowed along the side of the body of the microscope. A stationary post is screwed to an accessory fitting associated with the body of the microscope, and a filter holder, which includes a filter-retaining ring and an extending stem, is mounted for rotation from the end of the end of the post. To register the holder stabilized in its aligned and stowed positions, the stem rotates against a face of the post in which a groove is formed, and the stem is biased against the face by a spring so that it catches in the groove in either of the registered positions.