An electrostatically tunable Fabry-Perot interferometer produced by surface micromechanical techniques is used in optical material analysis as an optical sweeping filter in which the optical measurement wavelength is centered at a wavelength .lambda.. The Fabry-Perot interferometer based sensor structure comprises a body block, two essentially parallel mirrors bonded to the body block, of which mirrors at least one is partially transmitting and movable relative to the body block. The mirrors are...

Apparatus for detecting the existance of a source of coherent radiation in the presence of incoherent radiation. A beam splitter splits the radiation into two paths. Means are included in one path for transmitting the incoherent radiation and modulated coherent radiation. The other path effectively transmits only the incoherent radiation. Balancing means are used to balance out the incoherent radiation transmitting only the modulated coherent radiation which is then detected.

An electrostatically controlled, tunable Fabry-Perot interferometer is provided with a first, fixed mirror (4) to which a floating electrode (2) is fitted, a second, movable mirror (6) to which first and second control electrodes (8, 10) are fitted, and a resonant cavity of length d, defined by the first and second mirrors. The application of an electrical voltage between the two control electrodes operates to cause displacement of the movable mirror in relation to the fixed mirror, thereby modi...

A Fabry-Perot resonator, also called a Fabry-Perot cavity, is a spectroscopic device of extremely high resolving power and is a very useful tool for alignment of mask and wafer for the multiple exposures necessary to make a semiconductor integrated circuit. When a Fabry-Perot cavity is used for alignment in a multi-exposure imaging procedure, the cavity itself must be very accurately aligned for each exposure. For proper alignment system operation, it is necessary that one of the mirrors of the ...

A measuring apparatus comprises a sensor having a vibrating beam whose resonant frequency represents a parameter, such as pressure, to be measured. A light guide supplies light from a source to the beam and returns light reflected from the beam and from the end of the guide to an interferometer. The difference in light paths is greater than the coherent length of the light. The interferometer has first and second paths which differ in length by the difference in the light paths plus an odd numbe...

A system for the processing of materials includes a freezing section and a thawing section, with elongated channels extending through both sections, and gates between the sections and at the output of the thawing section. Large blocks of frozen material are slid from the freezing section to the thawing section; and a new batch of material is frozen with the heat from the freezing section used to thaw the blocks of frozen material. A harvest bar with dogs extending into the frozen material traver...

Broadband energy incident on a transducer having partially or fully reflective surfaces separated by a gap which is greater than the coherence length of the broadband energy but smaller than one-half a coherence length of a band of energy within said broadband energy causes a portion of the spectral content of the broadband energy corresponding to a coherence length greater than twice the gap length to exhibit interference effects while the average power of the broadband energy remains unaffecte...

The present invention relates to a press working process whereby a front cover and an impeller shell are deformed such that corner portions are formed on a blank material whereby the corner portions undergo minimal reductions in thickness. In the press working method, compressive force is applied parallel to the thickness of the blank to circumvent reduction in thickness during the deforming process.

This invention relates to an optical sensor for testing a biochemical sample. The sensor includes a resonant mirror device 1 and a prism 2 disposed adjacent the device 1 for coupling an input beam of light to the device 1. The input beam of light having a comb spectrum with a uniform spacing between adjacent lines or bands of the spectrum is produced by a comb spectrum source 10. The comb spectrum may be produced by a diode laser with multiple longitudinal modes. The input beam of light is polar...

A laser light, whose wavelength is to be measured, is introduced into an etalon, a concentric circular interference stripe derived from the etalon is irradiated onto a one-dimensional photodetector array and a diameter of the interference stripe is measured to measure the wavelength of the laser light. Alternatively, if a reference laser light of known wavelength is introduced into the etalon, as described above, a wavelength measurement of extremely high accuracy can be made without being affec...