Quantex Corporation

Kowa Company Limited

Other

Suganda Jutamulia

George M Storti

Joseph Lindmayer

William Seiderman

Shinji Toyoda

Charles Y Wrigley

Akihiro Fujita

Hideaki Niwa

Atsushi Kojima

Emeric I Podraczky

Eiichi Ito

To measure the coherence length of light, an incident beam (20) is caused to interfere with replicas of itself after having variable delays. Variable delays are generated by passing a beam (40) that is a part of the incident beam (20) around a loop (46). The beam partially leaves the loop (46) at each cycle and partially continues looping. A beam (44) with multiple delays leaving from the loop (46) is caused to interfere with a beam (56) that is another part of the incident beam (20) without delay, to create an output beam (60). The intensity of output beam (60) is affected by multiple delays caused by the loop (46), and depends on the coherence length of the incident beam (20). Therefore, the coherence length of the incident beam (20) can be obtained by detecting the intensity of output beam (60). When the coherence length of light is sufficiently large, by setting the resultant intensity of output beam (60) to be zero, the interferometer can also be used for high speed switching of laser light, based on a transient phenomenon.

Interferometers for measuring coherence length and high-speed switching

The mirror in a single-lens-reflex (SLR) camera is eliminated by employing a liquid crystal cell and a polarizing beam splitter. The light from an illuminating lamp (32) is linearly polarized in a horizontal direction by a polarizer (58). The polarized illuminating light is totally reflected by a polarizing beam splitter (PBS) (54) and passes through a quarterwave plate (QWP) (56) and an objective lens (36). After passing through QWP (56) for the second time, the light is vertically polarized and totally passes through PBS (54). A focusing lens (40) focuses the image onto a film (30). A voltage supply (46) is connected to a liquid-crystal (LC) cell (44) by an electric switch (52) that can turn LC cell (44) on or off. When LC cell (44) is off, the polarization of the light is rotated by 90.degree. to be horizontally polarized. Thus the light is reflected by another PBS (48) to a prism (24) for viewing by a user (26). When the LC cell (44) is on, the light polarization is not rotated, and the light is transmitted through the PBS (48) to a mechanical shutter (28). During the shutter's (28) open period, an intense light pulse from a strobe lamp (42) illuminates a patient's eye (38) and exposes film (30). Shutter (28) can be eliminated since the LC cell (44) and the PBS (48) may also function as shutter.

Liquid-crystal image director for single-lens-reflex camera

A vector-matrix multiplier in which a matrix is stored in an electron trapping material by exposing the material to visible light passed through a liquid crystal device, which acts as a mask. The visible light raises electrons in the electron trapping material to a higher energy level at the exposed locations. Infrared light is then passed through the liquid crystal device to form an input vector, which is projected onto the electron trapping material. The infrared light releases electrons from the higher energy level, resulting in emission of a pattern of visible light. The emission of visible light from the electron trapping material forms an output representing the product of the input vector and the matrix.

Compact vector-matrix multiplier system employing electron trapping

Continuous analytic transform functions implemented optically in U.S. Pat. No. 4,623,245 are instead implemented electronically and in real-time. An improved scheme is disclosed where the range of amplitudes of the monochromatic signal input is divided into n sections and constant, linear or sinusoidal transform functions are utilized in each section for transforming the monochromatic video input to three pseudocolor video signals. Even complex transform functions can be implemented by simple transform functions in each of the sections to reduce the overall complexity of the implementing circuit. The television camera, a pseudocolor encoder and a liquid crystal television monitor are placed within the same housing to form a portable hand-held unit. The weight and size of the unit can be reduced as a result of the simple electronic implementation of the encoder.

Real-time analytic pseudocolor encoder system

A method for using electron trapping materials to perform subtraction of images. One image is written onto a 2-dimensional screen of electron trapping material. A second image that has many of the elements of the first, but less than the total number of elements of the first, is erased from the electron trapping screen with infrared light. An exposure of the entire screen to infrared light results in luminescence output from those regions in which electrons remain trapped after the subtraction. Potential applications include machine inspection, image compression, etc. Images can be written on the screen of electron trapping material using energetic radiation or using short wavelength visible light.

Optical image subtraction employing electron trapping materials

A novel, high-speed spatial light modulator utilizing electron trapping materials. The electron trapping material is exposed to a pattern of modulating radiation, resulting in the excitation of electrons in the material at spatial locations corresponding to the pattern. When the light to be modulated (ordinarily coherent light) is simultaneously or subsequently passed through the material, it is absorbed in areas of the material where electrons have been excited. The unabsorbed light passes through the electron trapping material, producing a negative image of the pattern of modulating radiation. The electron trapping material also emits an image of incoherent visible light as the released electrons fall back to the ground state. This visible image can be filtered out if the device is only being used for modulating coherent light. Conversely, the device can be utilized by detecting only the incoherent visible emission from the electron trapping material, which constitutes a multiplicative product image of the electron exciting and electron releasing light incident on the electron trapping material.

Growing community of inventors

Fremont, CA, United States of America

Suganda Jutamulia