Patent EP0132956A2 successfully refreshed from Google Patents.
EP0132956A2
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Light beam scanning apparatus
Assignee: Fujitsu Ltd
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Filing: 1984-06-29
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Granted: —
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Expires: 2004-06-29
Abstract
Abstract In a light beam scanning apparatus using a hologram rotator (1), a post-hologram (9) is provided forfurther diffracting a light beam diffracted by the hologram rotatorto a direction opposite to that in which the light beam was first diffracted. By combining the kinds of wave fronts used for forming the holograms of the hologram rotator (1) and the post-hologram, the light beam scanning apparatus reduces deviation of the light beam scanning position caused by mode hopping of a laser diode, and an improved linear scanning of the light beam and/or image focusing characteristic is obtained.
Inventors
- 👤 Fumio Yamagishi
- 👤 Shinya Hasegawa
- 👤 Hiroyuki Ikeda
- 👤 Takefumi Inagaki
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-07 17:49
CPC Classifications
G; G06; G06K; G06K15/00; G06K15/02; G06K15/12; G06K15/1285; G02; G02B; G02B26/00; G02B26/08; G02B26/10; G02B26/106
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
38 words
A light beam scanning apparatus using a hologram rotator comprising a post-hologram including a spatial frequency for further diffracting a light beam to a direction opposite to that in which it is previously diffracted by the hologram rotator.
Claim 2
Dependent Claim
38 words
A light beam scanning apparatus using a hologram rotator comprising a post-hologram including a spatial frequency for further diffracting a light beam to a direction opposite to that in which it is previously diffracted by the hologram rotator.
Claim 3
Dependent Claim
16 words
An apparatus as set forth in claim 1, wherein the hologram rotator is a circular disk.
Claim 4
Dependent Claim
16 words
An apparatus as set forth in claim 1, wherein the hologram rotator has a cylindrical shape.
Claim 5
Dependent Claim
17 words
An apparatus as set forth in claim 1, wherein the hologram rotator has a circular cone shape..
Claim 6
Dependent Claim
28 words
1 to 4, 5. An apparatus as set forth in any of claims wherein a hologram formed on the hologram rotator is formed by two plane wave fronts.
Claim 7
Independent Claim
33 words
An apparatus as set forth in any of claims 1 to 4, wherein wave fronts for forming a hologram on the hologram rotator are a plane wave front and a divergent wave front.
Claim 8
Independent Claim
28 words
An apparatus as set forth in any of claims 1 to 4, wherein wave fronts for forming a hologram on the hologram rotator are two divergent wave fronts.
Claim 9
Independent Claim
33 words
An apparatus as set forth in any of claims 1 to 4, wherein wave fronts for forming a hologram on the hologram rotator are a convergent wave front and a divergent wave front.
Claim 10
Independent Claim
21 words
An apparatus as set forth in any preceding claim, wherein the post-hologram is registered with information providing a linear scanning characteristic.
Claim 11
Independent Claim
21 words
An apparatus as set forth in any preceding claim, wherein the post-hologram is registered with information providing an image focusing characteristic.
Claim 12
Independent Claim
23 words
An apparatus as set forth in any preceding claim,wherein wave fronts for forming a hologram on the post-hologram are two divergent wave fronts.
Claim 13
Independent Claim
32 words
An apparatus as set forth in any of claims 1 to 10, wherein wave fronts for forming a hologram on the post-tologram are a convergent wave front and a divergent wave front.
Claim 14
Independent Claim
32 words
An apparatus as set forth in any of claims 1 to 10 wherein wave fronts for forming a hologram on the post-hologram are a plane wave front and a divergent wave front.
Claim 15
Dependent Claim
53 words
A light beam scanning apparatus comprising a hologram rotator, for diffracting a light beam to a first direction, and a post hologram, for subsequently diffracting the light beam to a second direction away from the first direction and so as to cancel or reduce deviations due to wavelength changes of the light beam.
Claim 16
Dependent Claim
53 words
A light beam scanning apparatus comprising a hologram rotator, for diffracting a light beam to a first direction, and a post hologram, for subsequently diffracting the light beam to a second direction away from the first direction and so as to cancel or reduce deviations due to wavelength changes of the light beam.
Claim 17
Dependent Claim
21 words
A light beam scanning apparatus as claimed in any preceding claim, wherein said light beam is emitted by a laser diode.
References Cited (Backward Citations)
No citation records indexed.
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