Apparatus for determining the correlation of two electrical signals includes means converting the two signals into two acoustic beams. Coherent collimated light is passed through both acoustic beams. A Fourier transform of light through the beams is taken and this light is focused on detection means which measures the intensity of the light diffracted (and hence modulated) by the acoustic beams for determining the correlation of the electrical signals. In one embodiment, the two acoustic beams a...

Non-impact printing or recording apparatus adapted for use with a digital computer. The apparatus is characterized by the employment of an optical character generator and timing system therefor capable of printing information on a moving photoresponsive medium. The apparatus is further characterized by the provision of a field mask disposed intermediate a lens system and the photosensitive medium which field mask prevents projection of more than one character from a column of characters.

An interferometer employing a beam splitter, and means for circularly polarizing the split beams into mutually opposite directions. The circularly polarized beams are redirected to an analyzer, preferably rotational, to generate a phase interference pattern which is detected by photodetection devices.

A traffic signal apparatus for illuminating a message in alternate colors carries two light sources of different light color outputs. A one-way light mirror is positioned about one of the light sources to allow passage of light therefrom and to reflect substantially all light from an outside source such as the second light source. This optical system construction avoids unwanted light color reflection on a message plate of the housing during periods when the light source outside of the mirror is...

An optical encoder is provided with a new and improved exposure assembly comprising a readily replaceable exposure block fixedly mounting a plurality of individual light bulbs within a predetermined display pattern, a base for the exposure block supporting an apertured display mask within a code display station and aligning means on both the block and the base facilitating accurate and repeated aligned assembly of the block on the base without readjustment of the assembly.

Methods and apparatus are provided for the three-dimensional positioning by optical means of a head including simultaneous vertical and horizontal orientation for the taking sequentially of X-rays and/or photographs over a period of time in which the head is aligned exactly the same for each X-ray and/or photograph session in the sequence. In addition, preliminary substitution means are provided for aligning the apparatus prior to insertion of the head, thus eliminating prolonged exposure of a p...

A scanning device for a copying machine in which the original to be copied is stationary, the photosensitive paper moves on a conveyor, and a lens carriage moves at half the speed of the conveyor in the direction of its motion. The carriage rolls on wheels which rest on the conveyor and contact a fixed track from below, moving at half the speed of the conveyor because of the frictional contact of the wheels with the two parallel surfaces.

An optical comparator having workpiece support and a platform on which an enlarged layout of a profile can be laid and optical elements for reducing the image and causing it to coincide with an image of the workpiece itself, both the images being visible at the same scale through a microscope of the machine.

A visual display is disclosed in the form of a wine glass having a hollow stem, a doubled walled bowl with an interior chamber communicating with the stem and a bundle of optical fibers extending through the stem into the chamber where the terminal ends of the bundle are spread out by the chamber walls. A removable light, switch and battery package is mounted in the base of the glass for shining light into the fiber bundle.

An optical annunciator in which any one of alternate visual displays is revealed for viewing over the entire obverse surface of a lenticulate lens by the displacement of display means juxtaposed with the reverse surface of the lenticulate lens, the display means including alternate visual displays, each divided into portions, each portion of a display being located between adjacent portions of another display, and masking means for blocking from view those portions of the display means which do ...