Patent US3983509A successfully refreshed from Google Patents.
US3983509A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Distributed feedback diode laser
Assignee: Xerox Corp
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Filing: 1975-04-25
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Granted: 1976-09-28
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Expires: 1995-04-25
Abstract
Abstract A laser having layers of a first material interleaved with layers of a second material with the first material having a different index of refraction and bandgap than those of the second material. The thicknesses of the layers of the first and second materials satisfy the relationship t = m λ/2n where m is the laser mode and n is the index of refraction of the material, such that the right and left going waves of the light produced by the layers of the first material when the laser is pumped are coupled and reinforced in a coherent manner by the layers of the second material such that reflections from the second material are in phase, thus allowing laser operation in the absence of discrete end mirrors.
Inventors
- 👤 Donald R. Scifres
- 👤 Robert D. Burnham
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 21:59
CPC Classifications
H; H01; H01S; H01S5/00; H01S5/10; H01S5/18; H01S5/183; H01S5/18341; H01S5/04; H01S5/042; H01S5/0421; H01S5/0422; H01S5/0424; H01S5/18383
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
184 words
An electrically pumped multi-layered, diode laser comprising: a first plurality of layers of a first semiconductor material, a second plurality of layers of a second semiconductor material, said first and second semiconductor materials having different indices of refraction and different bandgaps, said second plurality of layers being interleaved with said first plurality of layers such that alternate layers of said laser are of different semiconductor material, each of said plurality of interleaved layers having a thickness t according to the relationship t = m λ/2n where m is an integer equal to the mode of the laser oscillations, λ is the wavelength of the light photons generated in the first plurality of layers when they are electrically pumped, and n is the refractive index of the material of said each layer, a rectifying junction extending through at least said first plurality of layers, and means for electrically pumping said first plurality of layers to produce said light photons of said wavelength whereby said light photons are coupled and reinforced in phase by said second plurality of layers to thereby provide a coherent output beam.
Claim 2
Dependent Claim
184 words
An electrically pumped multi-layered, diode laser comprising: a first plurality of layers of a first semiconductor material, a second plurality of layers of a second semiconductor material, said first and second semiconductor materials having different indices of refraction and different bandgaps, said second plurality of layers being interleaved with said first plurality of layers such that alternate layers of said laser are of different semiconductor material, each of said plurality of interleaved layers having a thickness t according to the relationship t = m λ/2n where m is an integer equal to the mode of the laser oscillations, λ is the wavelength of the light photons generated in the first plurality of layers when they are electrically pumped, and n is the refractive index of the material of said each layer, a rectifying junction extending through at least said first plurality of layers, and means for electrically pumping said first plurality of layers to produce said light photons of said wavelength whereby said light photons are coupled and reinforced in phase by said second plurality of layers to thereby provide a coherent output beam.
Claim 3
Dependent Claim
22 words
The laser of claim 1 wherein said first semiconductor material is gallium arsenide and said second semiconductor material is gallium aluminum arsenide.
Claim 4
Dependent Claim
30 words
The laser of claim 1 wherein said first plurality of layers extend beyond said second plurality of layers and said rectifying junction extends through only said first plurality of layers.
Claim 5
Dependent Claim
43 words
The laser of claim 1 wherein said first plurality of layers extend beyond said second plurality of layers and said rectifying junction extends through both said first and second plurality of layers near an edge of said first and second plurality of layers.
Claim 6
Dependent Claim
30 words
The laser of claim 1 wherein said rectifying junction extends through said first plurality of layers at an angle to the longitudinal surface planes of said first plurality of layers.
Claim 7
Dependent Claim
234 words
An electrically pumped, multi-layered diode laser comprising: a first plurality of layers of a first semiconductor material having an index of refraction n 1 , a second plurality of layers of a second semiconductor material having an index of refraction n 2 , said second plurality of layers being interleaved with said first plurality of layers such that alternate layers of said laser are of different semiconductor material, each of said first plurality of layers having a thickness t according to the relationship t = mλ/2n 1 and each of said second plurality of layers having a thickness t according to the relationship t = mλ/2n 2 where m is an integer equal to the mode of the laser oscillations and λ is the wavelength of the light photons generated in said first plurality of layers when they are electrically pumped, a rectifying junction extending through said first and second plurality of layers in a plane perpendicular to the longitudinal surfaces of said first and second plurality of layers, and means adjacent the plane of said rectifying junction for electrically pumping said multi-layered laser with voltage pulses having an amplitude and frequency such that only said first plurality of layers emit light photons with said light photons being of a wavelength that are reflected in phase by said second plurality of layers such that a coherent output light beam is omitted by the laser.
Claim 8
Dependent Claim
234 words
An electrically pumped, multi-layered diode laser comprising: a first plurality of layers of a first semiconductor material having an index of refraction n 1 , a second plurality of layers of a second semiconductor material having an index of refraction n 2 , said second plurality of layers being interleaved with said first plurality of layers such that alternate layers of said laser are of different semiconductor material, each of said first plurality of layers having a thickness t according to the relationship t = mλ/2n 1 and each of said second plurality of layers having a thickness t according to the relationship t = mλ/2n 2 where m is an integer equal to the mode of the laser oscillations and λ is the wavelength of the light photons generated in said first plurality of layers when they are electrically pumped, a rectifying junction extending through said first and second plurality of layers in a plane perpendicular to the longitudinal surfaces of said first and second plurality of layers, and means adjacent the plane of said rectifying junction for electrically pumping said multi-layered laser with voltage pulses having an amplitude and frequency such that only said first plurality of layers emit light photons with said light photons being of a wavelength that are reflected in phase by said second plurality of layers such that a coherent output light beam is omitted by the laser.
References Cited (Backward Citations)
US3737737A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-09-28 | 1980-03-29 | 1980-09-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-09-28 | 1984-03-29 | 1984-09-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-09-28 | 1988-03-29 | 1988-09-28 | $7700.00 | Window Closed / Lapsed |