US4636068A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Change-over shutter for light-wave range finder
Assignee: Pentax Corp
•
Filing: 1983-04-18
•
Granted: 1987-01-13
•
Expires: 2003-04-18
Abstract
Abstract A change-over shutter for an optical range finder employs at least two slits for measurement light, one of which is employed during long distance measurements and the other of which includes a light reduction member and is employed for short distance measurements. The arrangement advantageously eliminates measurement error caused in short distance measurements due to light secondarily reflected from the light emitting element.
Inventors
- 👤 Masaaki Niiho
- 👤 Kiyoshi Itoh
- 👤 Shinichi Suzuki
- 👤 Takuo Itagaki
- 👤 Koji Tsuda
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 12:27
CPC Classifications
G; G01; G01S; G01S7/00; G01S7/48; G01S7/481; G01S7/4811
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
49 words
A change-over shutter for a light-wave range finder for changing over between measurement light and compensation light, comprising; a shutter body having a plurality of measurement light slits and at least one compensation slit, and a light-quantity reducing member provided in at least one of said measurement light slits.
Claim 2
Dependent Claim
49 words
A change-over shutter for a light-wave range finder for changing over between measurement light and compensation light, comprising; a shutter body having a plurality of measurement light slits and at least one compensation slit, and a light-quantity reducing member provided in at least one of said measurement light slits.
Claim 3
Dependent Claim
17 words
A change-over shutter as described in claim 1, wherein said light-quantity reducing member comprises a density filter.
Claim 4
Dependent Claim
17 words
A change-over shutter as described in claim 1, wherein said light-quantity reducing member comprises a mesh-like element.
Claim 5
Dependent Claim
24 words
A change-over shutter as described in claim 1, wherein said light-quantity reducing member comprises means for narrowing at least one of said measurement slits.
Claim 6
Dependent Claim
29 words
A change-over shutter as described in claim 1, wherein said at least one measurement light slit provided with said light-quantity reducing member comprises a short-distance measurement measurement light slit.
Claim 7
Dependent Claim
38 words
A change-over shutter as described in claim 1, wherein said shutter body includes a pair of said measurement light slits at a predetermined angular interval, said light-quantity reducing member being provided in one of said measurement light slits.
Claim 8
Dependent Claim
25 words
A change-over shutter as described in claim 1, wherein said shutter body includes a pair of compensation light slits arranged at a predetermined angular interval.
Claim 9
Dependent Claim
25 words
A change-over shutter as described in claim 7, said compensation light slits and said measurement light slits being alternately angularly arranged in a non-overlapped manner.
Claim 10
Dependent Claim
24 words
A change-over shutter as described in claim 6, wherein the other of said measurement light slits comprises a long distance measurement measurement light slit.
Claim 11
Dependent Claim
44 words
A change-over shutter for light-wave range finder comprising a shutter body having at least one measurement light slit and at least one compensation light slit, and means for reducing amounts of secondarily reflected stray light passing through said measurement slit, thereby eliminating measurement error.
Claim 12
Dependent Claim
44 words
A change-over shutter for light-wave range finder comprising a shutter body having at least one measurement light slit and at least one compensation light slit, and means for reducing amounts of secondarily reflected stray light passing through said measurement slit, thereby eliminating measurement error.
Claim 13
Dependent Claim
55 words
A change-over shutter for a light-wave range finder comprising a shutter having at least one measurement light slit and at least one compensation light slit, and means for reducing amounts of secondarily reflected stray light passing through said measurement slit, thereby eliminating measurement error in short distance measurements otherwise caused by secondarily reflected stray light.
Claim 14
Dependent Claim
55 words
A change-over shutter for a light-wave range finder comprising a shutter having at least one measurement light slit and at least one compensation light slit, and means for reducing amounts of secondarily reflected stray light passing through said measurement slit, thereby eliminating measurement error in short distance measurements otherwise caused by secondarily reflected stray light.
Claim 15
Dependent Claim
61 words
A change-over shutter for a light-wave range finder comprising a shutter body having first means for making long distance measurements and second means for making short distance measurements, said first means having at least one first measurement light slit, and said second means having at least one second measurement light slit different from said at least one first measurement light slit.
Claim 16
Dependent Claim
61 words
A change-over shutter for a light-wave range finder comprising a shutter body having first means for making long distance measurements and second means for making short distance measurements, said first means having at least one first measurement light slit, and said second means having at least one second measurement light slit different from said at least one first measurement light slit.
References Cited (Backward Citations)
US578147A
Cited
CA486484A
Cited
US2734435A
Cited
US3500050A
Cited
US3619058A
Cited
US4101221A
Cited
US4165919A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-01-12 | 1990-07-14 | 1991-01-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-01-12 | 1994-07-14 | 1995-01-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-01-12 | 1998-07-14 | 1999-01-13 | $7700.00 | Window Closed / Lapsed |