US3652159A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Rangefinder for measuring the distance of an object having a luminous spot
Assignee: Paillard SA
•
Filing: 1969-09-15
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Granted: 1972-03-28
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Expires: 1989-09-15
Abstract
Abstract A rangefinder for measuring the distance of an object having a luminous spot has a convergent optical receiving system for picking up rays from the spot and converging them on to a sensing device. This device has a mirror wherein the edges of the reflective surface thereof comprises a separator element including a peripheral separating line sensitive to the convergence of the rays, and is arranged substantially on the caustic of the optical receiving system at a point remote from the optical axis of the system. The system may be at least one annular portion of a convergent system devoid of its central part. The caustic may have a cusp for greater concentration of light on said edges of the reflective surface of the mirror. The converging system may be formed by at least a part of a ring of a convergent system of lenses or of a concave Mangin mirror. The light projection device may be located on the axis of the optical system and in front of the photosensitive device, in the case where the central part of the optical system is not used.
Inventors
- 👤 Christian Lietar
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 18:50
CPC Classifications
G; G02; G02B; G02B17/00; G02B17/08; G02B17/0856; G02B19/00; G02B19/0004; G02B19/0028; G02B19/0033; G02B19/0076
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
205 words
In a rangefinder for measuring the distance of an object having a luminous spot and wherein a convergent optical receiving system is adapted to pick up rays from said spot and to make them converge on an edge of a sensing device sensitive to the distance of convergence of the said rays, the improvement, wherein said convergent optical receiving system includes a portion of a Mangin mirror corresponding to a zone of said mirror for which the caustic forms a cusp, said sensing device including a separator element movable along the optical axis of said convergent optical receiving system to remain substantially adjacent the area generated by said cusp of said caustic when the distance of the object to be measured is varied within the useful range of the range finder, said separator element separating the luminous flux forming the cusp portion of said caustic into two separate beams with the proportion of the luminous fluxes forming the two beams being dependent on the position of said separator element with respect to that of the cusp portion of said caustic and said sensing device including photoelectric means adapted to detect the intensity of the luminous fluxes of the two beams separated by said separator element.
Claim 2
Dependent Claim
205 words
In a rangefinder for measuring the distance of an object having a luminous spot and wherein a convergent optical receiving system is adapted to pick up rays from said spot and to make them converge on an edge of a sensing device sensitive to the distance of convergence of the said rays, the improvement, wherein said convergent optical receiving system includes a portion of a Mangin mirror corresponding to a zone of said mirror for which the caustic forms a cusp, said sensing device including a separator element movable along the optical axis of said convergent optical receiving system to remain substantially adjacent the area generated by said cusp of said caustic when the distance of the object to be measured is varied within the useful range of the range finder, said separator element separating the luminous flux forming the cusp portion of said caustic into two separate beams with the proportion of the luminous fluxes forming the two beams being dependent on the position of said separator element with respect to that of the cusp portion of said caustic and said sensing device including photoelectric means adapted to detect the intensity of the luminous fluxes of the two beams separated by said separator element.
Claim 3
Dependent Claim
28 words
A rangefinder according to claim 1, wherein the convergent optical system is constituted by at least one annular portion of a convergent system devoid of its central part.
Claim 4
Dependent Claim
26 words
A rangefinder according to claim 2, including a light projection device located on the axis of the optical system and in front of the sensing device.
Claim 5
Dependent Claim
27 words
A rangefinder according to claim 1, wherein the convergent optical system is formed by at least a part of a ring of a convergent system of lenses.
Claim 6
Dependent Claim
22 words
A rangefinder according to claim 1, wherein the convergent optical system is formed by two diametrically opposite portions of a Mangin mirror.
Claim 7
Dependent Claim
22 words
A rangefinder according to claim 1, wherein the convergent optical system is formed by a ring of a convergent system of lenses.
Claim 8
Dependent Claim
21 words
A rangefinder according to claim 1, wherein the convergent optical system is formed by a ring of a concave Mangin mirror.
Claim 9
Dependent Claim
29 words
A rangefinder according to claim 1, wherein the Mangin mirror is produced of a glass having a refractive index of about 1.51 and an Abbe number of about 64.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-03-28 | 1975-09-27 | 1976-03-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-03-28 | 1979-09-27 | 1980-03-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-03-28 | 1983-09-27 | 1984-03-28 | $7700.00 | Window Closed / Lapsed |