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US4476519A Expired / Lapsed US ⏱️ 0.0 years remaining

Annular illumination device

Assignee: Olympus Corp
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Filing: 1982-08-10
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Granted: 1984-10-09
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Expires: 2002-08-10
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Abstract

Abstract An annular illumination device comprising a tubular light transmitter, a light source means able to project parallel light rays onto an entrance end face of the tubular light transmitter from a direction intersecting diagonally with the entrance end face and a light collecting lens collecting conical light bundle coming out of an exit end face of the tubular light transmitter to form an image of an annular light in order to make it possible to make a bright efficient annular illumination. The angle formed by the parallel light rays with the entrance end face of the tubular light transmitter can be varied in order to vary the diameter of the image of the annular light.

Inventors

  • 👤 Toshisada Hayamizu

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 01:24
CPC Classifications
G; G02; G02B; G02B21/00; G02B21/06; G02B21/08; G02B21/14

Claims Analysis

Total Claims: 8
Claim 1
Independent Claim 120 words
An annular illumination device comprising a light source means capable of projecting substantially parallel light rays, a tubular light transmitter having its entrance end face and its exit end face both inclined to said light rays and capable of transmitting said light rays with its inner face reflections, a light collecting lens arranged so that its front focal point coincides with the exit end face of said tubular light transmitter and capable of collecting a conical light bundle projected out of the exit end face of said tubular light transmitter to form an image of an annular light, and a condenser lens arranged so that its front focal point coincides with a rear focal point of said light collecting lens.
Claim 2
Dependent Claim 120 words
An annular illumination device comprising a light source means capable of projecting substantially parallel light rays, a tubular light transmitter having its entrance end face and its exit end face both inclined to said light rays and capable of transmitting said light rays with its inner face reflections, a light collecting lens arranged so that its front focal point coincides with the exit end face of said tubular light transmitter and capable of collecting a conical light bundle projected out of the exit end face of said tubular light transmitter to form an image of an annular light, and a condenser lens arranged so that its front focal point coincides with a rear focal point of said light collecting lens.
Claim 3
Dependent Claim 40 words
An annular illumination device according to claim 1 wherein said light source means can move to vary the angle formed by said light rays with said entrance end face to vary the diameter of the image of said annular light.
Claim 4
Dependent Claim 44 words
An annular illumination device according to claim 1 or 2 wherein said tubular light transmitter is a member selected from the group consisting of optical fibers, a glass bar and a hollow pipe finished on the inner surface so as to be well reflective.
Claim 5
Dependent Claim 46 words
An annular illumination device according to claim 1 or 2 wherein said tubular light transmitter is formed of flexible optical fibers to vary the angle formed by said light rays with said entrance end face to vary the diameter of the image of said annular light.
Claim 6
Dependent Claim 20 words
An annular illumination device according to claim 1 or 2 wherein said light source means is a laser light source.
Claim 7
Dependent Claim 30 words
An annular illumination device according to claim 1 wherein said light source means consists of a xenon discharge tube as a light source, a collector lens and a relay lens.
Claim 8
Dependent Claim 69 words
An annular illumination device according to claim 1 or 2 wherein said tubular light transmitter is formed of flexible optical fibers to vary the angle formed by said light rays with said entrance end face to vary the diameter of the image of said annular light and wherein said light source means consists of a xenon discharge tube as a light source, a collector lens and a relay lens.

References Cited (Backward Citations)

US3600594A Cited
US3669524A Cited
US3663822A Cited
JPS4832124A Cited
US4072416A Cited
US3922618A Cited
JPS522442A Cited
US4054364A Cited
US4042823A Cited
US4361863A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1987-10-09 1988-04-09 1988-10-09 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1991-10-09 1992-04-09 1992-10-09 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1995-10-09 1996-04-09 1996-10-09 $7700.00 Window Closed / Lapsed

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