Patent US5034764A successfully refreshed from Google Patents.
US5034764A
Expired / Lapsed
US
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Combined eye- and waist-level real image mode finder
Assignee: Olympus Corp
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Filing: 1990-03-07
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Granted: 1991-07-23
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Expires: 2010-03-07
Abstract
Abstract A combined eye- and waist-level real image mode finder is equipped with an objective lens, a first eyepiece, a second eyepiece arranged so that an optical axis is inclined at a predetermined angle with respect to the first eyepiece, and a light beam splitting device disposed between the objective lens and the first and second eyepieces and splitting a light beam coming from the objective lens so that one part of the light beam is incident on the first eyepiece and the other part is incident on the second eyepiece. This finder has therefore important advantages in practical use that even in a status devoid of space to place an eye at an eye point and a case of sudden shutter chance, the field of the picture to be photographed is viewed with a favorable visual field factor, imaging performance and diopter, an image is bright, a twin image is not produced, a field mask is easily set, size is compact, the number of parts is small even in the case of being used as a zoom finder, and parallax is not generated.
Inventors
- 👤 Tatsuo Inabata
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 11:26
CPC Classifications
G; G02; G02B; G02B17/00; G02B17/02; G02B23/00; G02B23/14; G03; G03B; G03B13/00; G03B13/02; G03B13/06; G03B2213/00; G03B2213/02; G03B2213/025
Claims Analysis
Total Claims: 40
Claim 1
Independent Claim
140 words
A combined eye- and waist-level real image mode finder comprising: a finder objective lens provided independently of a photographic objective lens; an optical member for erecting a real image formed by said finder objective lens; a first optical element for observing the real image formed by said finder objective lens; a second optical element whose optical axis is inclined at a predetermined angle with respect to said first optical element, for observing the real image formed by said finder objective lens; and light beam splitting means arranged between said finder objective lens and said first and second optical elements, for splitting a light beam coming from said finder objective lens so that one part of the light beam is incident on said first optical element and the other part of the light beam is incident on said second optical element.
Claim 2
Dependent Claim
140 words
A combined eye- and waist-level real image mode finder comprising: a finder objective lens provided independently of a photographic objective lens; an optical member for erecting a real image formed by said finder objective lens; a first optical element for observing the real image formed by said finder objective lens; a second optical element whose optical axis is inclined at a predetermined angle with respect to said first optical element, for observing the real image formed by said finder objective lens; and light beam splitting means arranged between said finder objective lens and said first and second optical elements, for splitting a light beam coming from said finder objective lens so that one part of the light beam is incident on said first optical element and the other part of the light beam is incident on said second optical element.
Claim 3
Dependent Claim
61 words
A finder according to claim 1, wherein said light beam splitting means comprises a first reflecting member and a second reflecting member and the light beam from said finder objective lens is incident on one of said first optical element and said second optical element by inserting selectively said first reflecting member and said second reflecting member into an optical path.
Claim 4
Dependent Claim
26 words
A finder according to claim 1, wherein said light beam splitting means is provided between an entrance surface and an exit surface of said optical member.
Claim 5
Dependent Claim
22 words
A finder according to claim 1, wherein said light beam splitting means is provided on an entrance side of said optical member.
Claim 6
Dependent Claim
22 words
A finder according to claim 1, wherein said light beam splitting means is provided on an exit side of said optical member.
Claim 7
Dependent Claim
24 words
A finder according to any one of the preceding claims, wherein said first optical element and said second optical element are comprised of eyepieces.
Claim 8
Dependent Claim
14 words
A finder according to claim 3, wherein said optical member comprises a Porro prism.
Claim 9
Dependent Claim
98 words
A finder according to claim 1, wherein said light beam splitting means transmits one part of the light beam from said finder objective lens and reflects the other part of the light beam to split the light beam into an optical path lying on a transmission side of said light beam splitting means for making said one part of the light beam incident on said first optical element and an optical path lying on a reflection side of said light beam splitting means for making said other part of the light beam incident on said second optical element.
Claim 10
Dependent Claim
36 words
A finder according to claim 8, wherein said optical member comprises a Porro prism and said light beam splitting means is constructed by cementing a half-mirror coated prism to a reflecting surface of said Porro prism.
Claim 11
Dependent Claim
15 words
A finder according to claim 9, wherein said half-mirror coated prism is a Porro prism.
Claim 12
Dependent Claim
24 words
A finder according to claims 9 or 10, wherein said half-mirror coated prism has a decentered optical element lens on an exit surface thereof.
Claim 13
Dependent Claim
23 words
A finder according to claims 9 or 10, wherein said half-mirror coated prism has a Fresnel lens surface on an exit surface thereof.
Claim 14
Dependent Claim
17 words
A finder according to claims 9 or 10, wherein said half-mirror coated prism is a triangular prism.
Claim 15
Dependent Claim
15 words
A finder according to claim 11, wherein said half-mirror coated prism is a triangular prism.
Claim 16
Dependent Claim
15 words
A finder according to claim 12, wherein said half-mirror coated prism is a triangular prism.
Claim 17
Dependent Claim
17 words
A finder according to claims 9 or 10, wherein said half-mirror coated prism is a Dach prism.
Claim 18
Dependent Claim
15 words
A finder according to claim 11, wherein said half-mirror coated prism is a Dach prism.
Claim 19
Dependent Claim
15 words
A finder according to claim 12, wherein said half-mirror coated prism is a Dach prism.
Claim 20
Dependent Claim
65 words
A finder according to claim 3, wherein said light beam splitting means comprises a transmitting portion forming an optical path lying on a transmission side thereof, directing the light beam toward said first optical element and a totally reflecting portion forming an optical path lying on a reflection side thereof, directing the light beam toward said second optical element disposed alternately in a plural each.
Claim 21
Dependent Claim
65 words
A finder according to claim 7, wherein said light beam splitting means comprises a transmitting portion forming an optical path lying on a transmission side thereof, directing the light beam toward said first optical element and a totally reflecting portion forming an optical path lying on a reflection side thereof, directing the light beam toward said second optical element disposed alternately in a plural each.
Claim 22
Dependent Claim
26 words
A finder according to claim 8, wherein a mirror is provided on the optical path lying on the transmission side of said light beam splitting means.
Claim 23
Dependent Claim
26 words
A finder according to claim 5, wherein a mirror is provided on an optical path lying on a transmission side of said light beam splitting means.
Claim 24
Dependent Claim
26 words
A finder according to claim 19, wherein a mirror is provided on an optical path lying on a transmission side of said light beam splitting means.
Claim 25
Dependent Claim
26 words
A finder according to claim 20, wherein a mirror is provided on an optical path lying on a transmission side of said light beam splitting means.
Claim 26
Dependent Claim
31 words
A finder according to claim 8, wherein a totally reflecting surface of a prism is provided on the optical path lying on the transmission side of said light beam splitting means.
Claim 27
Dependent Claim
31 words
A finder according to claim 5, wherein a totally reflecting surface of a prism is provided on an optical path lying on a transmission side of said light beam splitting means.
Claim 28
Dependent Claim
31 words
A finder according to claim 19, wherein a totally reflecting surface of a prism is provided on an optical path lying on a transmission side of said light beam splitting means.
Claim 29
Dependent Claim
31 words
A finder according to claim 20, wherein a totally reflecting surface of a prism is provided on an optical path lying on a transmission side of said light beam splitting means.
Claim 30
Dependent Claim
35 words
A finder according to any one of claims 21, 22, 24-26 or 28, wherein a reflecting Dach surface is configured on the optical path lying on the transmission side of said light beam splitting means.
Claim 31
Dependent Claim
35 words
A finder according to any one of claims 21, 22, 24-26 or 28, wherein a decentered optical element is disposed on an optical path lying on a reflection side of said light beam splitting means.
Claim 32
Dependent Claim
28 words
A finder according to claim 29, wherein a decentered optical element is disposed on an optical path lying on a reflection side of said light beam splitting means.
Claim 33
Dependent Claim
55 words
A finder according to claims 3, 4 or 5, wherein said light beam splitting means comprises a first exit surface directing the light beam toward said first optical element and a second exit surface at which an exit optical axis is inclined at a predetermined angle with regard to said first exit surface, disposed alternately.
Claim 34
Dependent Claim
50 words
A finder according to claim 1, wherein said light beam splitting means comprises a first reflecting member and the light beam from said finder objective lens is incident on one of said first optical element and said second optical element by inserting said first reflecting member into an optical path.
Claim 35
Dependent Claim
25 words
A finder according to claims 2 or 33, wherein at least one of said first reflecting member and said second reflecting member comprises a prism.
Claim 36
Dependent Claim
14 words
A finder according to claim 4, wherein said optical member comprises a Porro prism.
Claim 37
Dependent Claim
14 words
A finder according to claim 5, wherein said optical member comprises a Porro prism.
Claim 38
Dependent Claim
27 words
A finder according to claim 20, wherein a decentered lens is provided on said optical path lying on the transmission side of the light beam splitting means.
Claim 39
Dependent Claim
36 words
A finder according to claim 20, wherein a prism whose exit surface has a shape of a decentered lens is provided on said optical path lying on the transmission side of the light beam splitting means.
Claim 40
Dependent Claim
55 words
A finder according to claim 7, 35 or 36 wherein said light beam splitting means comprises a first exit surface directing the light beam toward said first optical element and a second exit surface at which an exit optical axis is inclined at a predetermined angle with regard to said first exit surface, disposed alternately.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-07-22 | 1995-01-21 | 1995-07-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-07-22 | 1999-01-21 | 1999-07-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-07-22 | 2003-01-21 | 2003-07-23 | $7700.00 | Window Closed / Lapsed |