Multi-spectral laser array and optical system

• US 20050147135A1
• Filed: 02/16/2005
• Published: 07/07/2005
• Est. Priority Date: 11/25/2002
• Status: Abandoned Application

• Current Assignee: Eastman Kodak Company
• Original Assignee: Eastman Kodak Company
• Inventors: Kurtz, Andrew F., Kahen, Keith B., Kruschwitz, Brian E.
• Application Number:
  US11/059,243
• Publication Number:
  US 20050147135A1
• Time in Patent Office: Days
• US Class Current: 372/23
• CPC Class Codes: H01S 5/005 Optical components external to the laser cavity, specially adapted therefor, e.g. for homogenisation or merging of the beams or for manipulating laser pulses, e.g. pulse shaping H01S5/026, H01S5/18388 take precedence
• CPC Class Codes: H01S 5/041 Optical pumping
• CPC Class Codes: H01S 5/18319 comprising a periodical structure in lateral directions
• CPC Class Codes: H01S 5/18383 with periodic active regions at nodes or maxima of light intensity
• CPC Class Codes: H01S 5/36 comprising organic materials
• CPC Class Codes: H01S 5/4075 Beam steering
• CPC Class Codes: H01S 5/4093 Red, green and blue [RGB] generated directly by laser action or by a combination of laser action with nonlinear frequency conversion
• CPC Class Codes: H01S 5/423 having a vertical cavity
• CPC Class Codes: H04N 9/3161 using laser light sources using laser beams scanning the display screen H04N9/3129

Abstract

An organic vertical cavity laser light producing device (10) comprises a substrate (20). A plurality of laser emitters (200) emits laser light in a direction orthogonal to the substrate. Each laser emitter within the plurality of laser emitters has a first lateral mode structure in a first axis orthogonal to the laser light direction and has a second lateral mode structure in a second axis orthogonal to both the laser light direction and the first axis. Each laser emitter comprises a first mirror provided on a top surface of the substrate (20) and is reflective to light over a predetermined range of wavelengths. An organic active region (40) produces laser light (350). A second mirror is provided above the organic active region and is reflective to light over a predetermined range of wavelengths. A pumping means excites the plurality of laser emitters.

Claims

1. A multi-spectral laser light source, comprising:

a) a substrate;

b) a plurality of laser emitters emitting laser light in a direction orthogonal to the substrate, wherein each laser emitter within said plurality of laser emitters has a first lateral mode structure in a first axis orthogonal to the laser light direction and has a second lateral mode structure in a second axis orthogonal to both the laser light direction and said first axis, each laser emitter comprising;

i) a first mirror provided on a top surface of the substrate and reflective to light over a predetermined range of wavelengths;

ii) an active region on a top surface of said first mirror for producing laser light;

iii) a second mirror on a top surface of said active region and reflective to light over a predetermined range of wavelengths;

c) a pumping means that excites said plurality of laser emitters; and

wherein said laser light emitted by said plurality of laser emitters to provide multi-spectral output, wherein a first group of laser emitters emits light at nominal wavelengths in one portion of the optical spectrum, and a second group of laser emitters emits light at nominal wavelengths in a second portion of the optical spectrum.

2. A multi-spectral laser light source according to claim 1 wherein said laser emitters are arranged in parallel rows, said laser emitters in said rows have a periodic pattern, wherein a length of each of said laser emitters, a gap between each adjacent pair of said laser emitters, or both are varied along a full extent of a given row.

3. A multi-spectral laser light source according to claim 1 wherein said laser emitters are arranged in parallel rows, said laser emitters in said rows have a periodic pattern, wherein a length of each of said laser emitters and a gap between each adjacent pair of said laser emitters is repeated along the full extent of a given row.

4. A multi-spectral laser light source according to claim 1 wherein said first lateral mode structure exhibits multi-mode lasing behavior;

and

wherein each of said laser emitters have said second lateral mode structure that exhibits a single mode lasing behavior.

5. A multi-spectral laser light source according to claim 1 wherein said laser light emitted by said plurality of laser emitters is arranged to vary within the visible spectrum;

wherein each of said laser emitters provides laser light at a given nominal emission wavelength with an emission spectral bandwidth; and

wherein said nominal emission wavelength is variable within the visible spectrum for said plurality of laser emitters, such that the given nominal emission wavelength for one group of one or more of said laser emitters is different than the given nominal emission wavelength for another group of one or more of said laser emitters.

6. A multi-spectral laser light source according to claim 5 wherein said laser light emitted by said plurality of laser emitters is arranged to vary within the visible spectrum to provide multiple color output;

and

wherein said plurality of laser emitters are arranged in three groups of laser emitters, the first of which emits light at nominal wavelengths in the blue portion of the spectrum, the second of which emits light at nominal wavelengths in the green portion of the spectrum, and the third of which emits light at nominal wavelengths in the red portion of the spectrum.

7. A multi-color laser array comprising:

a) a substrate;

b) a plurality of laser emitters emitting laser light in a direction orthogonal to the substrate, wherein each laser emitter within said plurality of laser emitters, has a first lateral mode structure in a first axis orthogonal to the laser light direction and has a second lateral mode structure in a second axis orthogonal to both the laser light direction and said first axis, each laser emitter comprising;

i) a first mirror provided on a top surface of the substrate and reflective to light over a predetermined range of wavelengths;

ii) an active region on a top surface of said first mirror for producing laser light;

iii) a second mirror on a top surface of said active region and reflective to light over a predetermined range of wavelengths;

c) a pumping means that excites said plurality of laser emitters;

d) an arrangement of said laser emitters such that said plurality of laser emitters to form an array, comprising one or more parallel rows of laser emitters, wherein, within a row of laser emitters, a series of said laser emitters are arranged in sequence to form a line of laser emitters that are an array direction;

wherein said parallel rows of laser emitters are arranged in a sequence along a cross array direction; and

wherein said laser light emitted by said plurality of laser emitters is arranged to vary within the visible spectrum to provide multi-color output, such that a group of laser emitters emits light at nominal wavelengths in one portion of the visible spectrum, and a second group of laser emitters emits light at nominal wavelengths in a second portion of the visible spectrum.

8. A multi-color laser array according to claim 7 wherein each of said laser emitters within said plurality of laser emitters has a first lateral mode structure, along a first axis that is aligned with said array direction, that exhibits multi-mode lasing behavior, and wherein each of said laser emitters within said plurality of laser emitters has a second lateral mode structure, along a second axis that is aligned with said cross array direction, that exhibits a single mode lasing behavior.

9. A multi-color laser array according to claim 8 wherein within each of said parallel rows of laser emitters, said laser emitters are arranged in a sequence having a periodic pattern, wherein the length of each of said laser emitters and the gap between each adjacent pair of said laser emitters is repeated along the full extent of a given row.

10. A multi-color laser array according to claim 9 wherein said periodic pattern is the same for all of said parallel rows of laser emitters.

11. A multi-color laser array according to claim 7 wherein said laser emitters provides laser light emitted in different portions of the visible spectrum, such that said plurality of laser emitters are arranged in three groups of laser emitters, the first of which emits light at nominal wavelengths in the blue portion of the spectrum, the second of which emits light at nominal wavelengths in the green portion of the spectrum, and the third of which emits light at nominal wavelengths in the red portion of the spectrum.

12. A multi-color laser array according to claim 11 wherein said laser emitters emit laser light at multiple nominal wavelengths within a given color spectrum selected from red, green or blue spectrum.

13. A multi-color laser array comprising:

a) a substrate;

b) a plurality of laser emitters emitting laser light in a direction orthogonal to the substrate, wherein each laser emitter within said plurality of laser emitters, has a first lateral mode structure in a first axis orthogonal to the laser light direction that corresponds to multi-mode lasing behavior and has a second lateral mode structure in a second axis orthogonal to both the laser light direction and said first axis that corresponds to single mode lasing behavior, each laser emitter comprising;

i) a first mirror provided on a top surface of the substrate and reflective to light over a predetermined range of wavelengths;

ii) an active region on a top surface of said first mirror for producing laser light;

iii) a second mirror on a top surface of said active region and reflective to light over a predetermined range of wavelengths;

c) a pumping means that excites said plurality of laser emitters;

d) an arrangement of said laser emitters within said plurality of laser emitters to form an array, comprising one or more parallel rows of laser emitters, wherein, within a row of laser emitters, a series of said laser emitters are arranged in sequence to form a line of laser emitters that are an array direction;

wherein said parallel rows of laser emitters are arranged in a sequence that is a cross array direction; and

wherein said laser light emitted by said plurality of laser emitters is arranged to vary within the visible spectrum to provide multi-color output, such that a group of laser emitters emits light at nominal wavelengths in one portion of the visible spectrum, and a second group of laser emitters emits light at nominal wavelengths in a second portion of the visible spectrum.

14. A multi-color laser array comprising:

a) a substrate;

b) a plurality of laser emitters emitting laser light in a direction orthogonal to the substrate, wherein each laser emitter within said plurality of laser emitters, has a first lateral mode structure in a first axis orthogonal to the laser light direction that corresponds to multi-mode lasing behavior and has a second lateral mode structure in a second axis orthogonal to both the laser light direction and said first axis that corresponds to multi-mode lasing behavior, wherein there are many fewer modes in the second axis direction than in the first axis direction, each laser emitter comprising;

i) a first mirror provided on a top surface of the substrate and reflective to light over a predetermined range of wavelengths;

ii) an active region on a top surface of said first mirror for producing laser light;

iii) a second mirror on a top surface of said active region and reflective to light over a predetermined range of wavelengths;

c) a pumping means that excites said plurality of laser emitters;

d) an arrangement of said laser emitters within said plurality of laser emitters to form an array, comprising one or more parallel rows of laser emitters, wherein, within a row of laser emitters, a series of said laser emitters are arranged in sequence to form a line of laser emitters that are an array direction;

wherein said parallel rows of laser emitters are arranged in a sequence that is a cross array direction; and

wherein said laser light emitted by said plurality of laser emitters is arranged to vary within the visible spectrum to provide multi-color output, such that a group of laser emitters emits light at nominal wavelengths in one portion of the visible spectrum, and a second group of laser emitters emits light at nominal wavelengths in a second portion of the visible spectrum.

15. A multi-color laser array according to claim 14 wherein said emitters emit light at nominal wavelengths that is in one of the primary colors.

16. A modulation optical system with a multi-spectral laser array comprising:

a) a multi-spectral laser array comprising;

i) a substrate;

ii) a plurality of laser emitters emitting laser light in a direction orthogonal to the substrate, wherein each laser emitter within said plurality of laser emitters has a first lateral mode structure in a first axis orthogonal to the laser light direction and has a second lateral mode structure in a second axis orthogonal to both the laser light direction and said first axis, each laser emitter comprising;

a1) a first mirror provided atop the substrate and reflective to light over a predetermined range of wavelengths;

a2) an active region for producing laser light;

a3) a second mirror provided above the active region and reflective to light over a predetermined range of wavelengths;

a4) an arrangement of said laser emitters within said plurality of laser emitters to form an array, comprising one or more parallel rows of laser emitters, wherein, within a row of laser emitters, a series of said laser emitters are arranged in sequence to form a line of laser emitters in an array direction;

a5) a pumping means that excites said plurality of laser emitters;

wherein said parallel rows of laser emitters are arranged in a sequence in a cross array direction;

wherein said laser light emitted by said plurality of laser emitters is arranged to vary within the optical spectrum to provide multi-spectral output, such that a group of laser emitters emits light at nominal wavelengths in one portion of the optical spectrum, and a second group of laser emitters emits light at nominal wavelengths in a second portion of the optical spectrum;

b) optical means, comprising laser beam shaping optics for preparing laser light from said multi-spectral laser array to illuminate a spatial light modulator array; and

c) wherein said spatial light modulator array comprises an arrangement of individually addressed modulator pixels, each of which alter incident laser light in accordance with applied drive signals specific to each of said pixels.

17. A modulation optical system according to claim 16 wherein said first lateral mode structure is multi-mode and said second lateral mode structure is single mode.

18. A modulation optical system according to claim 16 wherein said laser array is multimode in both directions, with many fewer modes in the second axis direction than in the first axis direction.

19. A modulation optical system according to claim 16 wherein said laser array is single mode in the second axis direction, and multi-mode in the first axis direction, and the emitters extend nearly the full length of the array in the first axis direction.

20. An electronic imaging system with a multi-spectral laser array comprising:

a) one or more multi-spectral laser arrays, each comprising;

i) a substrate;

ii) a plurality of laser emitters emitting laser light in a direction orthogonal to the substrate, wherein each laser emitter within said plurality of laser emitters, has a first lateral mode structure in a first axis orthogonal to the laser light direction and has a second lateral mode structure in a second axis orthogonal to both the laser light direction and said first axis, each laser emitter comprising;

a1) a first mirror provided on atop the substrate and reflective to light over a predetermined range of wavelengths;

a2) an active region for producing laser light;

a3) a second mirror provided above the active region and reflective to light over a predetermined range of wavelengths;

a4) an arrangement of said laser emitters within said plurality of laser emitters to form an array, comprising one or more parallel rows of laser emitters, wherein, within a row of laser emitters, a series of said laser emitters are arranged in sequence to form a line of laser emitters in an array direction;

a5) a pumping means that excites said plurality of laser emitters;

wherein said parallel rows of laser emitters are arranged in a sequence in a cross array direction;

wherein said laser light emitted by said plurality of laser emitters is arranged to vary within the optical spectrum to provide multi-spectral output, such that a group of laser emitters emits light at nominal wavelengths in one portion of the optical spectrum, and a second group of laser emitters emits light at nominal wavelengths in a second portion of the optical spectrum;

b) optical means, comprising laser beam shaping optics for preparing laser light to illuminate a spatial light modulator array;

which comprises modulator pixels that are individually addressed with applied drive signals bearing data; and

c) imaging optics to re-image said spatial light modulator array onto a target plane.

21. An electronic imaging system according to claim 20 wherein said electronic imaging system is a printing system with a light sensitive media located at the target plane.

22. An electronic imaging system according to claim 20 wherein said first lateral mode structure is multi-mode and said second lateral mode structure is single mode.

23. An electronic imaging system according to claim 20 wherein said multi-spectral laser arrays provide light over a predetermined range of wavelengths comprising one or more of the primary colors.