US5995292A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for adjustable spherical aberration correction
Assignee: OPTITEK
•
Filing: 1998-06-16
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Granted: 1999-11-30
•
Expires: 2018-06-16
Abstract
Abstract A pair of compensation lenses which provide an adjustable amount of spherical aberration. Each compensation lens has an external surface and an internal surface. The internal surfaces face each other and define an air gap spacing between them. The external surfaces are preferably planar. The internal surfaces are purely aspheric and therefore have an absence of spherical power and an absence of spherical curvature. The amount of spherical aberration compensation is determined by adjusting an air gap spacing between the internal surfaces. The spherical aberration provided by the lenses can be negative, positive, or zero. For compensation of negative spherical aberration present when focusing light into a data storage medium, the compensation lenses should provide positive spherical aberration. The absence of spherical power characteristic of the compensation lenses allows them to be located far from an objective lens which requires spherical aberration compensation. Also, the absence of spherical power renders the focusing characteristics of an optical system independent from the air gap spacing thickness. Further, absence of spherical power renders the numerical aperture of the optical system unchanged by variations in air gap spacing.
Inventors
- 👤 Mark McDonald
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 00:24
CPC Classifications
G; G02; G02B; G02B27/00; G02B27/0025; G11; G11B; G11B7/00; G11B7/12; G11B7/135; G11B7/1372; G11B7/1378; G11B2007/0003; G11B2007/0009; G11B2007/0013
Claims Analysis
Total Claims: 44
Claim 1
Independent Claim
121 words
An apparatus for providing spherical aberration in a light beam, the apparatus comprising: a) a first optical element having an aspheric refractive characteristic and a first internal surface; b) a second optical element having an aspheric refractive characteristic and a second internal surface, the second element being disposed adjacent to the first element such that an air gap spacing is defined between the first and second internal surfaces, and wherein the optical elements are disposed such that the light beam passes through the first optical element before entering the second optical element; wherein the first internal surface and the second internal surface have complementary shapes; whereby the amount of spherical aberration is determined by a thickness of the air gap spacing.
Claim 2
Independent Claim
121 words
An apparatus for providing spherical aberration in a light beam, the apparatus comprising: a) a first optical element having an aspheric refractive characteristic and a first internal surface; b) a second optical element having an aspheric refractive characteristic and a second internal surface, the second element being disposed adjacent to the first element such that an air gap spacing is defined between the first and second internal surfaces, and wherein the optical elements are disposed such that the light beam passes through the first optical element before entering the second optical element; wherein the first internal surface and the second internal surface have complementary shapes; whereby the amount of spherical aberration is determined by a thickness of the air gap spacing.
Claim 3
Dependent Claim
20 words
The apparatus of claim 1 wherein the first optical element and the second optical element together provide positive spherical aberration.
Claim 4
Dependent Claim
22 words
The apparatus of claim 1 wherein the first optical element and the second optical element each have an infinitely long focal length.
Claim 5
Dependent Claim
23 words
The apparatus of claim 1 wherein the first optical element has a diverging characteristic and the second optical element has a converging characteristic.
Claim 6
Dependent Claim
23 words
The apparatus of claim 1 wherein the first optical element has a converging characteristic and the second optical element has a diverging characteristic.
Claim 7
Dependent Claim
14 words
The apparatus of claim 1 wherein the first optical element is a GRIN lens.
Claim 8
Dependent Claim
14 words
The apparatus of claim 1 wherein the second optical element is a GRIN lens.
Claim 9
Dependent Claim
14 words
The apparatus of claim 1 wherein the first optical element is an aspheric lens.
Claim 10
Dependent Claim
14 words
The apparatus of claim 1 wherein the second optical element is an aspheric lens.
Claim 11
Dependent Claim
21 words
The apparatus of claim 1 wherein the first optical element and the second optical element each have purely aspheric refractive characteristics.
Claim 12
Dependent Claim
26 words
The apparatus of claim 1 wherein the first optical element is an aspheric lens and the first internal surface is aspheric and neither concave or convex.
Claim 13
Dependent Claim
26 words
The apparatus of claim 1 wherein the second optical element is an aspheric lens and the second internal surface is aspheric and neither concave or convex.
Claim 14
Independent Claim
161 words
An apparatus for providing spherical aberration and focusing of a light beam, the apparatus comprising: a) a first optical element having an aspheric refractive characteristic and a first internal surface; b) a second optical element having an aspheric refractive characteristic and a second internal surface, the second element being disposed adjacent to the first element such that an air gap spacing is defined between the first and second internal surfaces, and wherein the optical elements are disposed such that the light beam passes through the first optical element before entering the second optical element; and c) an objective lens assembly disposed coaxial with the first optical element and the second optical element and located such that the light beam passes through the second optical element before passing through the objective lens; wherein the first internal surface and the second internal surface have complementary shapes; whereby the amount of spherical aberration compensation is determined by a thickness of the air gap spacing.
Claim 15
Independent Claim
161 words
An apparatus for providing spherical aberration and focusing of a light beam, the apparatus comprising: a) a first optical element having an aspheric refractive characteristic and a first internal surface; b) a second optical element having an aspheric refractive characteristic and a second internal surface, the second element being disposed adjacent to the first element such that an air gap spacing is defined between the first and second internal surfaces, and wherein the optical elements are disposed such that the light beam passes through the first optical element before entering the second optical element; and c) an objective lens assembly disposed coaxial with the first optical element and the second optical element and located such that the light beam passes through the second optical element before passing through the objective lens; wherein the first internal surface and the second internal surface have complementary shapes; whereby the amount of spherical aberration compensation is determined by a thickness of the air gap spacing.
Claim 16
Dependent Claim
22 words
The apparatus of claim 13 wherein the first optical element and the second optical element each have an infinitely long focal length.
Claim 17
Dependent Claim
23 words
The apparatus of claim 13 wherein the first optical element has a diverging characteristic and the second optical element has a converging characteristic.
Claim 18
Dependent Claim
23 words
The apparatus of claim 13 wherein the first optical element has a converging characteristic and the second optical element has a diverging characteristic.
Claim 19
Dependent Claim
20 words
The apparatus of claim 13 wherein the first optical element and the second optical element together provide positive spherical aberration.
Claim 20
Dependent Claim
16 words
The apparatus of claim 13 further comprising an actuator means for varying the air gap spacing.
Claim 21
Dependent Claim
35 words
The apparatus of claim 13 wherein the first optical element and the second optical element together have a focal length which is at least 10 times longer than the focal length of the objective lens.
Claim 22
Dependent Claim
35 words
The apparatus of claim 19 wherein the first optical element and the second optical element together have a focal length which is at least 100 times longer than the focal length of the objective lens.
Claim 23
Dependent Claim
21 words
The apparatus of claim 13 wherein the first optical element and the second optical element each have purely aspheric refractive characteristics.
Claim 24
Independent Claim
124 words
An apparatus for providing spherical aberration in a light beam, the apparatus comprising: a) a first compensation lens having a first external surface and a convex internal surface, wherein the convex internal surface has an aspheric shape; b) a second compensation lens having a second external surface and a concave internal surface, wherein the concave internal surface has an aspheric shape, the second compensation lens being disposed with respect to the first compensation lens such that the convex internal surface and the concave internal surface face each other and define an air gap spacing therebetween; wherein the convex internal surface and the concave internal surface have complementary shapes; whereby the amount of spherical aberration is determined by a thickness of the air gap spacing.
Claim 25
Independent Claim
124 words
An apparatus for providing spherical aberration in a light beam, the apparatus comprising: a) a first compensation lens having a first external surface and a convex internal surface, wherein the convex internal surface has an aspheric shape; b) a second compensation lens having a second external surface and a concave internal surface, wherein the concave internal surface has an aspheric shape, the second compensation lens being disposed with respect to the first compensation lens such that the convex internal surface and the concave internal surface face each other and define an air gap spacing therebetween; wherein the convex internal surface and the concave internal surface have complementary shapes; whereby the amount of spherical aberration is determined by a thickness of the air gap spacing.
Claim 26
Dependent Claim
12 words
The apparatus of claim 22 wherein the internal surfaces are purely aspheric.
Claim 27
Dependent Claim
11 words
The apparatus of claim 22 wherein the external surfaces are planar.
Claim 28
Dependent Claim
16 words
The apparatus of claim 22 further comprising an actuator means for varying the air gap spacing.
Claim 29
Dependent Claim
20 words
The apparatus of claim 22 wherein the first compensation lens and the second compensation lens together provide positive spherical aberration.
Claim 30
Dependent Claim
22 words
The apparatus of claim 22 wherein the first compensation lens and the second compensation lens each have an infinitely long focal length.
Claim 31
Dependent Claim
43 words
The apparatus of claim 22 wherein the first compensation lens and the second compensation lens are disposed such that the light beam enters the first compensation lens through the first external surface and exits the second compensation lens through the second external surface.
Claim 32
Dependent Claim
43 words
The apparatus of claim 22 wherein the first compensation lens and the second compensation lens are disposed such that the light beam enters the second compensation lens through the second external surface and exits the first compensation lens through the first external surface.
Claim 33
Independent Claim
146 words
An apparatus for providing spherical aberration compensation and focusing of a light beam, the apparatus comprising: a) a first compensation lens having a first external surface and a convex internal surface, wherein the convex internal surface has an aspheric shape; b) a second compensation lens having a second external surface and a concave internal surface, wherein the concave internal surface has an aspheric shape, the second compensation lens being coaxially disposed with respect to the first compensation lens such that the convex internal surface and the concave internal surface face each other and define an air gap spacing therebetween; c) an objective lens assembly disposed coaxial with the first compensation lens and the second compensation lens; wherein the convex internal surface and the concave internal surface have complementary shapes; whereby the amount of spherical aberration compensation is determined by a thickness of the air gap spacing.
Claim 34
Independent Claim
146 words
An apparatus for providing spherical aberration compensation and focusing of a light beam, the apparatus comprising: a) a first compensation lens having a first external surface and a convex internal surface, wherein the convex internal surface has an aspheric shape; b) a second compensation lens having a second external surface and a concave internal surface, wherein the concave internal surface has an aspheric shape, the second compensation lens being coaxially disposed with respect to the first compensation lens such that the convex internal surface and the concave internal surface face each other and define an air gap spacing therebetween; c) an objective lens assembly disposed coaxial with the first compensation lens and the second compensation lens; wherein the convex internal surface and the concave internal surface have complementary shapes; whereby the amount of spherical aberration compensation is determined by a thickness of the air gap spacing.
Claim 35
Dependent Claim
22 words
The apparatus of claim 30 wherein the objective lens is disposed closer to the second compensation lens than the first compensation lens.
Claim 36
Dependent Claim
11 words
The apparatus of claim 30 wherein the external surfaces are planar.
Claim 37
Dependent Claim
35 words
The apparatus of claim 30 wherein the first compensation lens and the second compensation lens together have a focal length which is at least 10 times longer than the focal length of the objective lens.
Claim 38
Dependent Claim
35 words
The apparatus of claim 33 wherein the first compensation lens and the second compensation lens together have a focal length which is at least 100 times longer than the focal length of the objective lens.
Claim 39
Dependent Claim
20 words
The apparatus of claim 30 wherein the first compensation lens and the second compensation lens together provide positive spherical aberration.
Claim 40
Dependent Claim
22 words
The apparatus of claim 30 wherein the first compensation lens and the second compensation lens each have an infinitely long focal length.
Claim 41
Dependent Claim
43 words
The apparatus of claim 30 wherein the first compensation lens and the second compensation lens are disposed such that the light beam enters the first compensation lens through the first external surface and exits the second compensation lens through the second external surface.
Claim 42
Dependent Claim
43 words
The apparatus of claim 30 wherein the first compensation lens and the second compensation lens are disposed such that the light beam enters the second compensation lens through the second external surface and exits the first compensation lens through the first external surface.
Claim 43
Dependent Claim
16 words
The apparatus of claim 30 further comprising an actuator means for varying the air gap spacing.
Claim 44
Dependent Claim
12 words
The apparatus of claim 30 wherein the internal surfaces are purely aspheric.
References Cited (Backward Citations)
US5105408A
Cited
US5097464A
Cited
US5235581A
Cited
US5125750A
Cited
US5677903A
Cited
US5202875A
Cited
US5610901A
Cited
US5157555A
Cited
US5726436A
Cited
US5526181A
Cited
US5497359A
Cited
JPH08212579A
Cited
EP0727777A1
Cited
US5712842A
Cited
JPH08315404A
Cited
US5764613A
Cited
US5729393A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2002-11-29 | 2003-05-31 | 2003-11-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-11-29 | 2007-05-31 | 2007-11-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-11-29 | 2011-05-31 | 2011-11-30 | $7700.00 | Window Closed / Lapsed |