Light deflecting device

• US 5,323,259 A
• Filed: 10/30/1992
• Issued: 06/21/1994
• Est. Priority Date: 12/23/1991
• Status: Expired due to Fees

• Current Assignee: Fujifilm Electronic Imaging Ltd. (Fujifilm Holdings Corporation)
• Original Assignee: Crosfield Electronics Ltd. (Fujifilm Holdings Corporation)
• Inventors: Gibbs, Ronald
• Primary Examiner(s): Sugarman, Scott J.
• Assistant Examiner(s): Phan, James
• Application Number:
  US07/969,397
• Time in Patent Office: 599 Days
• Field of Search: 359/209, 359/211, 359/831, 359/833-834, 359/837, 359/900
• US Class Current: 359/211.1
• CPC Class Codes: G02B 26/0816 by means of one or more reflecting elements
• CPC Class Codes: G02B 26/10 Scanning systems
• CPC Class Codes: G02B 27/0031 for scanning purposes
• CPC Class Codes: G02B 27/642 Optical derotators, i.e. systems for compensating for image rotation, e.g. using rotating prisms, mirrors
• CPC Class Codes: H04N 1/0635 using oscillating or rotating mirrors
• CPC Class Codes: H04N 1/0657 Scanning a transparent surface, e.g. reading a transparency original

Abstract

A light deflecting device for use in a light scanner, comprises a deflector (4) and a dove prism (13) mounted together on a rotatable support (16). The support (16) rotates about a nominal axis (2) coaxial with an incident light beam direction (11). A beam is incident on the deflector (4) so as to be deflected through a fixed angle (Θ) relative to the nominal axis (2) independently of any angular movement of the support (16) about the nominal axis.

Claims

1. A light deflecting device for use in a light scanner, the device comprising a common rotatable support, a deflector and a dove prism mounted together on said rotatable support which rotates about a nominal axis coaxial with an incident light beam direction, wherein a light beam is incident on the dove prism and thereafter on the deflector so as to be deflected through a fixed angle relative to the nominal axis independently of any angular, non-rotational movement of the support about said nominal axis.

2. A device according to claim 1, wherein a dove prism is a truncated isosceles right angle prism.

3. A device according to claim 1, wherein the scanner is an internal drum scanner.

4. A device according to claim 1, wherein said deflector is one of a front coated mirror, a rear coated mirror and a right-angle prism.

5. A method of operating a light deflecting device in a light scanner, the method comprising:

mounting a dove prism and light deflector together on a common support;

applying an incident light beam to the dove prism and thereafter to the deflector, whilst rotating the support about a nominal axis coaxial with the incident light beam direction;

the foregoing steps being performed such that the incident light beam is deflected through a fixed angle relative to the nominal axis independently of any angular, non-rotational movement of the support about said nominal axis.