Abstract: A spherometer for measuring at least one physical parameter of the workpiece includes at least on fluid-actuated linearly extensible probe member having an output indicative of an amount of linear travel and a chamber housing the linearly extensible probe member. The chamber has an aperture for supporting a workpiece and a vacuum line is coupled to the chamber for creating a vacuum. The probe member is activated as a result of the vacuum in the chamber, causing it to extend linearly toward the workpiece until touching it. The linear extension of the probe may be used as a measurement of distance. The distance measured to a workpiece may be compared to a standard to determine a physical parameter of the workpiece.

Abstract: The present invention provides a stable tripod stand for sensitive optical devices such as telescopes and the like. The tripod may be moved around on wheels which are coupled to casters and when positioned may be secured to the ground to provide an adjustable and highly stable support that significantly reduces the incidence of jitter. The tripod includes a stabilizer member that extends through the casters to selectively engage the ground. The leg members of the tripod have a triangular shape and support links between the platform and the leg members form interlocking triangular supports which reinforce the leg members.

Abstract: The present invention provides a telescope having a focal plane into which an image of a distant object is focused. It includes a primary mirror and a secondary mirror wherein the secondary mirror is positioned to cast a shadow on a portion of the primary mirror. A data image projecting device projects a data image from the portion of the primary mirror which lies in the shadow of the secondary mirror. The data image is focused in the focal plane of the telescope and is superimposed on the image of the distant object.