← Back to Patent Explorer
US3944334A Expired / Lapsed US ⏱️ 0.0 years remaining

Acousto-optic filter

Assignee: Panasonic Holdings Corp
•
Filing: 1974-08-27
•
Granted: 1976-03-16
•
Expires: 1994-08-27
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract An acousto-optic filter utilizing the far-off-axis anisotropic Bragg diffraction comprising an optically anisotropic acousto-optic medium embodied by paratellurite. The light entrance surface is slanted to the crystalline axis to make a light beam incident perpendicularly to the surface. The light exit surface is slanted to the direction of the entrance surface to minimize the dispersion of diffracted angle due to light wave length.

Inventors

  • 👤 Tsutomu Yano
  • 👤 Akinori Watanabe

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 17:05
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/11; G02F1/116

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 146 words
An acousto-optic filter comprising: a medium in which light has two different phase velocities in a propagating direction, said medium having entrance and exit surfaces for light rays, transducer means for propagating an ultrasonic wave in said medium, and means for directing a light beam to the entrance surface of said medium so as to cause far-off-axis anisotropic Bragg diffraction with said ultrasonic wave, said diffraction occurring at a relatively large incident angle with respect to the plane of the wave front of said ultrasonic wave in said medium, the propagation direction of the diffracted light being displaced from the plane of the wave front of said ultrasonic wave in the same direction as that of undiffracted light to produce optical filtering, the entrance surface of said medium being slanted by a predetermined angle from the plane normal to the wave front of the ultrasonic wave.
Claim 2
Dependent Claim 146 words
An acousto-optic filter comprising: a medium in which light has two different phase velocities in a propagating direction, said medium having entrance and exit surfaces for light rays, transducer means for propagating an ultrasonic wave in said medium, and means for directing a light beam to the entrance surface of said medium so as to cause far-off-axis anisotropic Bragg diffraction with said ultrasonic wave, said diffraction occurring at a relatively large incident angle with respect to the plane of the wave front of said ultrasonic wave in said medium, the propagation direction of the diffracted light being displaced from the plane of the wave front of said ultrasonic wave in the same direction as that of undiffracted light to produce optical filtering, the entrance surface of said medium being slanted by a predetermined angle from the plane normal to the wave front of the ultrasonic wave.
Claim 3
Dependent Claim 15 words
An acousto-optic filter according to claim 1, wherein said medium is a paratellurite single crystal.
Claim 4
Dependent Claim 59 words
An acousto-optic filter according to claim 1, wherein the normal direction of the exit surface of said medium is slanted from the normal of the acoustic wave front by a different angle from that of the entrance surface so as to minimize the variation in the exit angle of a transmitted light beam due to variations in the wavelength.
Claim 5
Dependent Claim 15 words
An acousto-optic filter according to claim 3, wherein said medium is a paratellurite single crystal.
Claim 6
Dependent Claim 22 words
An acousto-optic filter according to claim 4, wherein said acoustic wave is propagated along the <110> direction of the paratellurite single crystal.
Claim 7
Dependent Claim 41 words
An acousto-optic filter according to claim 5, wherein the normals of the entrance surface and the acoustic wave front make an angle of 20° and the normals of the exit surface and the acoustic wave front make an angle of 16°41'.

References Cited (Backward Citations)

No citation records indexed.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1979-03-16 1979-09-15 1980-03-16 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1983-03-16 1983-09-15 1984-03-16 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1987-03-16 1987-09-15 1988-03-16 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag