Patent
Acousto-optic band reject light filter and apparatus using same
TLDR
In this article, an acousto-optic band reject light filter is described, in which an acoustic wave is excited at a selected radio frequency corresponding to a selected optical frequency to be rejected.Abstract:
An acousto-optic band reject light filter is disclosed. The light filter includes an optically anisotropic medium, such as a birefringent crystal, in which an acoustic wave is excited at a certain selected radiofrequency corresponding to a selected optical frequency to be rejected. The crystal is disposed to receive an incident light beam containing the selected optical frequency to be rejected. The light beam is collinearly diffracted on the acoustic wave within the optically anisotropic medium to diffract light of a first polarization and of the selected optical frequency related to the acoustic frequency into light of a second polarization. The diffracted light beam is then passed through a polarization analyzer to reject from the diffracted light beam light of the second polarization while retaining in the diffracted light beam light of the first polarization. The selectable frequency in the light beam which is to be rejected can be tuned over a wide band by tuning the frequency of the acoustic wave within the crystal.read more
Citations
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Patent
Electronically tuneable light source
TL;DR: In this paper, an electronically tuneable light source includes a source (10) of white light, an acousto-optic modulator (16) which includes a transparent medium and means (17) for generating an acoustic wave in the medium, and means for directing the collimated beam of the white light onto the medium at a preselected angle θ/2 to a line which is perpendicular to the direction of travel of the acoustical wave.
Patent
Negotiable instrument fraud detector and processor
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Method and device for controlling the amplitude of the wavelength spectrum of ultra-short light pulses emitted by multipass laser amplifiers
TL;DR: In this paper, a programmable acousto-optic device is introduced into a laser cavity of a multipass amplifier, in order to modify slightly the amplitude of the spectrum of the light pulse with each passage, owing to a collinear or quasi-collinear interaction between the light pulses and a sound beam.
Patent
Intermediate-web held terminal pins
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References
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Journal ArticleDOI
Electronically tunable acousto‐optic filter
TL;DR: In this article, a tunable optical filter with a band pass of less than 2 A, a corrected peak transmission of 50%, and an average skirt rejection ratio of about 45 dB have been obtained.
Patent
Monochromator wavelength drives
TL;DR: A stepping-motor may be driven at variable rates by supplying a series of evenly-spaced (in time) PULSES at any particULAR DESIRED RATE as mentioned in this paper.
Patent
Solid-state image display device with acoustic scanning of strain-responsive semiconductor
TL;DR: In this paper, a solid state television-type image display device includes a panel of strain-responsive semiconductor material whose absorption edge in the unstrained condition is at a first predetermined wavelength, but in response to strain the absorption edge moves to a second predetermined wavelength shorter than the first.