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US4687285A Expired / Lapsed US ⏱️ 0.0 years remaining

Device for coupling a light source and an optical waveguide

Assignee: US Philips Corp
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Filing: 1985-10-02
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Granted: 1987-08-18
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Expires: 2005-10-02
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Abstract

Abstract A device for coupling a light source and an optical waveguide. The light source has an emissive surface whose dimensions are of the same order of magnitude as or smaller than the cross-sectional dimension of the waveguide. The coupling device comprises a ball lens, which is contact with the light source, and a convergent optical transfer system. The optical transfer system images the input face of the waveguide to the optical center of the ball lens with a magnification of approximately -1. The radiation issuing from any point of the emissive surface of the light source enters the waveguide as parallel rays.

Inventors

  • 👤 Claude E. Hily
  • 👤 Jacqueline-Madeleine Michel

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-25 16:41
CPC Classifications
G; G02; G02B; G02B6/00; G02B6/24; G02B6/42; G02B6/4201; G02B6/4204; G02B6/4206

Claims Analysis

Total Claims: 23
Claim 1
Independent Claim 154 words
A device for coupling a light source and an optical waveguide, said waveguide having an input face, said device comprising: a light source having an emissive surface with a size less than or equal to that of the input face of the optical waveguide; a ball lens arranged in contact with the light source, said ball lens having a center; and a convergent optical system arranged between the ball lens and the input face of the waveguide, said optical system forming an image of the input face with a magnification of approximately -1 in the center of the ball lens; characterized in that: the ball lens and the optical system has a focal point; and the emissive surface of the light source is arranged at the focal point of the ball lens and the optical system so that rays emitted from any point on the emissive surface enter the waveguide as a parallel beam.
Claim 2
Independent Claim 154 words
A device for coupling a light source and an optical waveguide, said waveguide having an input face, said device comprising: a light source having an emissive surface with a size less than or equal to that of the input face of the optical waveguide; a ball lens arranged in contact with the light source, said ball lens having a center; and a convergent optical system arranged between the ball lens and the input face of the waveguide, said optical system forming an image of the input face with a magnification of approximately -1 in the center of the ball lens; characterized in that: the ball lens and the optical system has a focal point; and the emissive surface of the light source is arranged at the focal point of the ball lens and the optical system so that rays emitted from any point on the emissive surface enter the waveguide as a parallel beam.
Claim 3
Independent Claim 206 words
A device for coupling a light source and an optical waveguide, said waveguide having an input face, said device comprising: a light source having an emissive surface with a size less than or equal to that of the input face of the optical waveguide; a ball lens arranged in contact with the light source, said ball lens having a center; and a convergent optical system arranged between the ball lens and the input face of the waveguide, said optical system forming an image of the input face with a magnification of approximately -1 in the center of the ball lens; characterized in that: the ball lens and the optical system has a focal point; the emissive surface of the light source is arranged at the focal point of the ball lens and the optical system so that rays emitted from any point on the emissive surface enter the waveguide as a parallel beam; the ball lens is held in contact with the light source by an adhesive; and the adhesive, the ball lens, and the emissive surface have indices of refraction, said adhesive having an index of refraction between the index of refraction of the ball lens and the index of refraction of the emissive surface.
Claim 4
Independent Claim 206 words
A device for coupling a light source and an optical waveguide, said waveguide having an input face, said device comprising: a light source having an emissive surface with a size less than or equal to that of the input face of the optical waveguide; a ball lens arranged in contact with the light source, said ball lens having a center; and a convergent optical system arranged between the ball lens and the input face of the waveguide, said optical system forming an image of the input face with a magnification of approximately -1 in the center of the ball lens; characterized in that: the ball lens and the optical system has a focal point; the emissive surface of the light source is arranged at the focal point of the ball lens and the optical system so that rays emitted from any point on the emissive surface enter the waveguide as a parallel beam; the ball lens is held in contact with the light source by an adhesive; and the adhesive, the ball lens, and the emissive surface have indices of refraction, said adhesive having an index of refraction between the index of refraction of the ball lens and the index of refraction of the emissive surface.
Claim 5
Dependent Claim 17 words
A device as claimed in claim 1, characterized in that the light source is a light-emitting diode.
Claim 6
Dependent Claim 45 words
A device as claimed in claim 3, characterized in that: the light-emitting diode has an outer surface; and the emissive surface has a diameter on the order of 30 microns and is located at most 5 microns from the outer surface inside the light-emitting diode.
Claim 7
Dependent Claim 32 words
A device as claimed in claim 4, characterized in that the optical waveguide is a graded index waveguide having a core diameter of 50 microns and a numerical aperture of approximately 0.2.
Claim 8
Dependent Claim 32 words
A device as claimed in claim 4, characterized in that the optical waveguide is a graded index waveguide having a core diameter of 85 microns and a numerical aperture of approximately 0.2.
Claim 9
Dependent Claim 24 words
A device as claimed in claim 4, characterized in that the optical system and the input face of the waveguide are separated by air.
Claim 10
Dependent Claim 26 words
A device as claimed in claim 4, characterized in that the optical system and the input face of the waveguide are separated by a transparent plate.
Claim 11
Dependent Claim 33 words
A device as claimed in claim 8, characterized in that the device further comprises a protective housing in which the light source is arranged, the transparent plate forming a window in the housing.
Claim 12
Independent Claim 297 words
A device for coupling a light source and an optical waveguide, said waveguide having an input face, said device comprising: a light source having an emissive surface with a size less than or equal to that of the input face of the optical waveguide; a ball lens arranged in contact with the light source, said ball lens having a center; and a convergent optical system arranged between the ball lens and the input face of the waveguide, said optical system forming an image of the input face with a magnification of approximately -1 in the center of the ball lens; characterized in that: the ball lens and the optical system has a focal point; the emissive surface of the light source is arranged at the focal point of the ball lens and the optical system so that rays emitted from any point on the emissive surface enter the waveguide as a parallel beam; the optical system comprises first and second identical planoconvex lenses, each lens having a plane surface and a convex surface, said lenses being arranged with their convex surfaces facing each other; the plane surface of the first lens faces the input face of the waveguide, the optical distance between the plane surface of the first lens and the input face of the waveguide being D 1 ; the plane surface of the second lens faces the ball lens, the optical distance between the plane surface of the second lens and the center of the ball lens being D 2 ; D 1 is substantially equal to D 2 ; and the lenses have optical axes which pass through the center of the ball lens and which are normal to the input face of the waveguide and to the emissive surface of the light source.
Claim 13
Independent Claim 297 words
A device for coupling a light source and an optical waveguide, said waveguide having an input face, said device comprising: a light source having an emissive surface with a size less than or equal to that of the input face of the optical waveguide; a ball lens arranged in contact with the light source, said ball lens having a center; and a convergent optical system arranged between the ball lens and the input face of the waveguide, said optical system forming an image of the input face with a magnification of approximately -1 in the center of the ball lens; characterized in that: the ball lens and the optical system has a focal point; the emissive surface of the light source is arranged at the focal point of the ball lens and the optical system so that rays emitted from any point on the emissive surface enter the waveguide as a parallel beam; the optical system comprises first and second identical planoconvex lenses, each lens having a plane surface and a convex surface, said lenses being arranged with their convex surfaces facing each other; the plane surface of the first lens faces the input face of the waveguide, the optical distance between the plane surface of the first lens and the input face of the waveguide being D 1 ; the plane surface of the second lens faces the ball lens, the optical distance between the plane surface of the second lens and the center of the ball lens being D 2 ; D 1 is substantially equal to D 2 ; and the lenses have optical axes which pass through the center of the ball lens and which are normal to the input face of the waveguide and to the emissive surface of the light source.
Claim 14
Dependent Claim 63 words
A device as claimed in claim 10, characterized in that: the ball lens is held in contact with the light source by an adhesive; and the adhesive, the ball lens and the emissive surface have indicies of refraction, said adhesive having an index of refraction between the index of refraction of the ball lens and the index of refraction of the emissive surface.
Claim 15
Dependent Claim 17 words
A device as claimed in claim 11, characterized in that the light source is a light-emitting diode.
Claim 16
Dependent Claim 45 words
A device as claimed in claim 12, characterized in that: the light-emitting diode has an outer surface; and the emissive surface has a diameter on the order of 30 microns and is located at most 5 microns from the outer surface inside the light-emitting diode.
Claim 17
Dependent Claim 32 words
A device as claimed in claim 13, characterized in that the optical waveguide is a graded index waveguide having a core diameter of 50 microns and a numerical aperture of approximately 0.2.
Claim 18
Dependent Claim 32 words
A device as claimed in claim 13, characterized in that the optical waveguide is a graded index waveguide having a core diameter of 85 microns and a numerical aperture of approximately 0.2.
Claim 19
Dependent Claim 24 words
A device as claimed in claim 13, characterized in that the optical system and the input face of the waveguide are separated by air.
Claim 20
Dependent Claim 26 words
A device as claimed in claim 13, characterized in that the optical system and the input face of the waveguide are separated by a transparent plate.
Claim 21
Dependent Claim 33 words
A device as claimed in claim 17, characterized in that the device further comprises a protective housing in which the light source is arranged, the transparent plate forming a window in the housing.
Claim 22
Independent Claim 154 words
A device for coupling a light source and an optical waveguide, said waveguide having an input face, said device comprising: a light source having an emissive surface with a size less than or equal to that of the input face of the optical waveguide; a ball lens arranged in front of the light source, said ball lens having a center; and a convergent optical system arranged between the ball lens and the input face of the waveguide, said optical system forming an image of the input face with a magnification of approximately -1 in the center of the ball lens; characterized in that: the ball lens and the optical system has a focal point; and the emissive surface of the light source is arranged at the focal point of the ball lens and the optical system so that rays emitted from any point on the emissive surface enter the waveguide as a parallel beam.
Claim 23
Independent Claim 154 words
A device for coupling a light source and an optical waveguide, said waveguide having an input face, said device comprising: a light source having an emissive surface with a size less than or equal to that of the input face of the optical waveguide; a ball lens arranged in front of the light source, said ball lens having a center; and a convergent optical system arranged between the ball lens and the input face of the waveguide, said optical system forming an image of the input face with a magnification of approximately -1 in the center of the ball lens; characterized in that: the ball lens and the optical system has a focal point; and the emissive surface of the light source is arranged at the focal point of the ball lens and the optical system so that rays emitted from any point on the emissive surface enter the waveguide as a parallel beam.

References Cited (Backward Citations)

DE2926925A1 Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1990-08-17 1991-02-16 1991-08-18 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1994-08-17 1995-02-16 1995-08-18 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1998-08-17 1999-02-16 1999-08-18 $7700.00 Window Closed / Lapsed

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