Abstract: An infrared collimator uses a barrel and an infrared energy emitting source mounted at one end of the barrel. A reticle mask over the emission source produces a reticle beam pattern which is concentrated and collimated by a mirror assembly including a convex reflector mounted at a front end of the barrel and a concave concentrator with a central through bore and mounted in the barrel between the emission source and the convex reflector. The collimator produces infrared energy in a coherent, collimated beam pattern for instrument calibration and testing purposes.

Abstract: A multiple sensor inclination measuring system includes a plurality of single and dual axis inclination sensors, each sensor including a bridge circuit for generating a signal or pair of signals, each signal having a voltage which is proportional to the degree of inclination of the sensor, and an analog-to-digital converter to convert the signal to a digital word having a binary value representative of the tilt of the sensor. Each sensor is connected to a support unit which includes a microprocessor, memory, and data communication capabilities. Each support unit may include a look-up table which calibrates the unit specifically to the sensor used.

Abstract: A three dimension optical transit target for use in optical tooling, when a construction site of interest is not within view of optical transits, comprises a rod having a target head on one end and an engagement area on another end for contact with the construction site. The target head includes at least one target, preferably defined by cross-hairs, located on a line passing through a rotational axis of the rod and the construction site of interest when the three dimension target is in use. When the three dimension target is supported such that the cross-hairs are visible from a sufficient number of optical transits, the location of the construction site in relation to the transits may be determined if the distance between the cross-hairs and the construction site is known. Several embodiments are described; in one a single set of cross-hairs is used in a target head which, in use, is supported with the cross-hairs positioned on a vertical line passing through the site.

Abstract: A dual axis inclination measuring system includes a sensor unit for placement on a surface to determine the inclination of the surface with respect to two mutually perpendicular horizontal axes and an indicator unit connected to the sensor unit and operative to process signals generated by the sensor unit to determine and indicate the inclination of the test surface. The sensor unit includes a dual axis sensor element which cooperates with circuits for generating signals having voltage levels proportional to the inclination of the sensor. The indicator unit includes an analog-to-digital converter operative to convert the voltage levels to digital words and a digital computer operative to calculate angle readings from the digital words. The computer includes a look-up table of a plurality of the digital words stored in a memory of the computer and is calibrated exclusively to the particular sensor with which the computer is used, thereby providing great accuracy.

Abstract: A dual axis capacitive inclination sensor includes a flat cylindrical vial defined by a lower conductive half and an upper dielectric half with a chamber therebetween containing a dielectric liquid with a bubble therein. A top surface of the upper half has two pairs of axis capacitor plates positioned thereon in spaced relation to two mutually perpendicular horizontal inclination axes, and each of the axis plates forms a capacitor in cooperation with the lower half which functions as a common capacitor plate. Inclination of the vial about one or both of the inclination axes causes a change in the position of the bubble with respect to the capacitive system, thereby changing the capacitance between the plates. Each of the axis capacitor plates has a shape defined by a circumferentially extending web portion having inwardly directed radial portions connected at the opposite ends of the web.

Abstract: A precision optical square instrument for use in optical tooling to accurately determine lines and planes at right angles to each other, such as horizontal and vertical lines and planes. The instrument employs focusable telescopes mounted at right angles to each other and supported between spaced arms of a standard rotatably mounted on a spindle connected to a base, such as for rotation about a vertical axis. The standard has opposed arms with trunnions therein supporting a first telescope for rotation about an axis, such as horizontal, for creating a first plane of view and positioned perpendicularly of the axis of rotation of the standard about the spindle. The optical axis of a second telescope perpendicularly crosses the optical axis of the first telescope at the juncture of rotative axis of the spindle with the first telescope and is rotatable orthogonally to the optical axis of the first telescope for creating a second plane of view perpendicular to the first plane.