US3609012A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Optical condensing system with variable effective focal length
Assignee: SPINDLER AND SAUPPE Inc
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Filing: 1969-10-06
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Granted: 1971-09-28
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Expires: 1989-10-06
Abstract
Abstract A versatile optical condensing system readily convertible for use with projection lenses covering a wide range of focal lengths, as 35 to 250 mm. using a common group of lenses by themselves or in combination with a selected one in a second group of lenses. This system is characterized by its simplicity, compactness, highly uniform light intensity, minimal chromatic abberation and ability to hold the image size of the light source to a minimum at the entrance pupil of the projection lens to avoid the need for costly high-speed projection lenses. The basic lens system utilizes three lens the second and third of which each have one aspheric surface designed with controlled spherical abberation and so that the light rays passing between these two aspheric surfaces are substantially parallel to the optical axis. This feature makes it feasible to vary the axial spacing of these two lenses as necessary to accommodate the basic lens system for optimal use wit a selected supplemental condensing lens and one of several projection lenses of differing focal lengths. The invention makes it possible to manufacture of wide range of condensing system sizes at very substantial cost savings using a minimum number of variable components.
Inventors
- 👤 Chan Street
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 21:11
CPC Classifications
G; G02; G02B; G02B1/00; G02B13/00; G02B13/18; G02B15/00; G02B15/02; G02B19/00; G02B19/0004; G02B19/0009; G02B19/0014; G02B19/0033; G02B19/0047
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
147 words
An optical condensing system comprising a plurality of optical elements in axial alignment with a source of luminous radiation, said system including a pair of lens elements having an aspheric surface on each thereof cooperating with one another and with the other surfaces of said lens elements to distribute consecutive rays of the source radiation relative to the optical axis in accordance with a smoothly ordered function over a prescribed area of a plane forwardly of and normal to the axis of said condensing system and characterized in that said lens elements are so shaped an dispoSed relative to one another and to the source of luminous radiation as to direct rays passing through said lens elements into intersection with the optical axis of said system at a multiplicity of points distributed in the same consecutive order over a substantial length thereof forwardly of said condensing system.
Claim 2
Dependent Claim
147 words
An optical condensing system comprising a plurality of optical elements in axial alignment with a source of luminous radiation, said system including a pair of lens elements having an aspheric surface on each thereof cooperating with one another and with the other surfaces of said lens elements to distribute consecutive rays of the source radiation relative to the optical axis in accordance with a smoothly ordered function over a prescribed area of a plane forwardly of and normal to the axis of said condensing system and characterized in that said lens elements are so shaped an dispoSed relative to one another and to the source of luminous radiation as to direct rays passing through said lens elements into intersection with the optical axis of said system at a multiplicity of points distributed in the same consecutive order over a substantial length thereof forwardly of said condensing system.
Claim 3
Dependent Claim
51 words
An optical condensing system as defined in claim 1 characterized in that said optical system includes a first condensing lens element between said radiation source and a first one of said pair of lens elements and spanning an arc of at least 90* with respect to the source of luminous radiation.
Claim 4
Dependent Claim
71 words
An optical condensing system as defined in claim 1 characterized in that the aspheric surfaces respectively present on said pair of lens elements are so shaped and positioned that rays located closer to the optical axis in the zone of said lens elements intersect the optical axis at points more distantly from said lens element than the points of intersection of rays passing through the outer portions of said lens elements.
Claim 5
Dependent Claim
59 words
An optical condensing system as defined in claim 1 characterized in that said pairs of lens elements are so shaped and spaced from one another relative to the source of radiation as to provide an ordered distribution of the source rays in the plane normal to the optical axis and forwardly of the nearest one of said lens elements.
Claim 6
Dependent Claim
59 words
An optical condensing system as defined in claim 1 characterized in the combination therewith of a projection lens forwardly of said pair of lens elements and in which said rays are distributed in a smoothly ordered function, and said multiplicity of points of ray intersection with said optical axis being forwardly of the nodal point of said projection lens.
Claim 7
Dependent Claim
113 words
An optical condensing system as defined in claim 5 characterized in that said condensing system is selectively convertible for use with differing focal length projection lenses, said condensing system including a supplemental lens between said pair of lens and the object plane upon which the projection lens is focused and cooperating with said pair of lens elements to vary the angle of said radiation source rays relative to said optical axis so as to shift their respective points of intersection with the optical axis thereby to adapt said condensing system for use with a projection lens of a different focal length without need for relocating the radiation source relative to the object plane.
Claim 8
Dependent Claim
54 words
An optical condensing system as defined in claim 6 characterized in that said additional lens element is a positive element effective to increase the angle of the respective source rays relative to said optical axis in passing therethrough thereby to adapt said condensing system to use with a projection lens of shorter focal length.
Claim 9
Dependent Claim
53 words
An optical condensing system as defined in claim 9 characterized in that said additional lens element is a negative element effective to diminish the angle of respective source rays relative to said optical axis in passing therethrough thereby to adapt said condensing system to use with a projection lens of longer focal length.
Claim 10
Dependent Claim
52 words
An optical condensing system as defined in claim 6 characterized in that said additional lens and the adjacent one of said pair of lens elements are spaced from the other of said pair of lens elements by a distance varying with and dependent upon the design constants of said additional lens elements.
Claim 11
Dependent Claim
36 words
A condensing lens system as defined in claim 2 characterized in that said lens elements are arranged along the optical axis in the numerical order and having the design parameters set forth in table I, namely:
Claim 12
Dependent Claim
73 words
An optical condensing system as defined in claim 10 readily convertible for use with projection lens of widely differing focal lengths and characterized in the provision of a set of supplemental lens usable selectively in combination forwardly of the third lens of the lens system defined in claim 20 and which supplemental lens have the design parameters and relationships to the lenses operatively associated therewith set forth in tables II and III, namely:
Claim 13
Dependent Claim
28 words
A condensing lens system as defined in claim 10 characterized in the selective use therewith of one additional lens forwardly of lens III having the following constructional data:
References Cited (Backward Citations)
US2637242A
Cited
US3472577A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-09-27 | 1975-03-29 | 1975-09-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-09-27 | 1979-03-29 | 1979-09-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-09-27 | 1983-03-29 | 1983-09-28 | $7700.00 | Window Closed / Lapsed |