System and method for combining laser arrays for digital outputs

• US 8,613,536 B2
• Filed: 12/16/2010
• Issued: 12/24/2013
• Est. Priority Date: 12/19/2009
• Status: Active Grant

• Current Assignee: Lumentum Operations, LLC (Lumentum Holdings Inc.)
• Original Assignee: TriLumina Corp
• Inventors: Joseph, John R., Wiedemann, Rudolf A.
• Primary Examiner(s): Williams, Joseph L
• Application Number:
  US12/970,880
• Publication Number:
  US 20110148328A1
• Time in Patent Office: 1,104 Days
• Field of Search: 362/553, 362/19, 362/235, 362/231, 362/552, 362/259
• US Class Current: 362/553
• CPC Class Codes: F21K 9/00 Light sources using semiconductor devices as light-generating elements, e.g. using light-emitting diodes [LED] or lasers
• CPC Class Codes: G02B 6/4214 the intermediate optical element having redirecting reflective means, e.g. mirrors, prisms for deflecting the radiation from horizontal to down- or upward direction toward a device G02B6/4246 takes precedence
• CPC Class Codes: H01S 5/4012 Beam combining, e.g. by the use of fibres, gratings, polarisers, prisms

Abstract

Embodiments comprise a device that can efficiently produce a highly resolved intensity profile that can be easily switched to various specific configurations with binary word strings defining output intensities that after summation will be combined to form a single colors intensity depth. Arraying these devices allows an image line of single color pixels to be efficiently produced without gross scintillation effects. The non-coherent output is desirable in this application as it reduces scintillation effects on the screen or final image.

Claims

1. A system for combining the output of a plurality of semiconductor light devices to generate a digital output, comprising:

a first set of semiconductor light devices among the plurality of semiconductor light devices and operable to generate a plurality of first wavelengths, the first set of semiconductor light devices grouped in a first shape within at least one array of one or more sub-arrays;

a first binary string containing digital output data, each bit from the first binary string controlling a power of each sub-array from the one or more sub-arrays, wherein a wavelength intensity generated by each sub-array is determined by a position of a particular bit controlling each sub-array; and

a first beam combiner combining the plurality of first wavelengths to generate a first wavelength beam representative of the digital output.

2. The system as recited in claim 1, further comprising:

a second set of semiconductor light devices among the plurality of semiconductor light devices and operable to generate a plurality of second wavelengths, the second set of semiconductor light devices grouped in a second shape within at least one second array of one or more second sub-arrays;

a second binary string containing second digital output data, each bit from the second binary string controlling a power of each second sub-array from the one or more second sub-arrays, wherein a second wavelength intensity generated by each second sub-array is determined by the position of the particular bit controlling each second sub-array;

a second beam combiner combining the plurality of second wavelengths to generate a second wavelength beam; and

a non-coherent beam combiner combining the first wavelength beam and a second wavelength beam to generate a plurality of data points corresponding to the digital output.

3. The system as recited in claim 1, wherein the plurality of semiconductor light devices is selected from the group consisting of a top emitting vertical-cavity surface emitting laser (VCSEL), a bottom emitting VCSEL, a top emitting VCSEL with external cavities (VECSEL), and a bottom emitting VECSEL.

4. The system as recited in claim 1, wherein the plurality of semiconductor light devices is selected from the group consisting of a light-emitting diode, an edge emitting laser, an organic light-emitting diode, an optically pumped light source, and an electrically pumped light source.

5. The system as recited in claim 1, wherein a most significant bit sub-array among the one or more sub-arrays has a larger number of semiconductor light devices than a least significant bit array among the one or more sub-arrays.

6. The system as recited in claim 1, wherein each semiconductor light device within a most significant bit sub-array among the one or more sub-arrays has a larger aperture size than each semiconductor light device within a least significant bit sub-array among the one or more sub-arrays.

7. The system as recited in claim 1, wherein semiconductor light devices within a sub-array are connected in parallel and are driven by a single connection.

8. The system as recited in claim 7, wherein the single connection acts as a thermal management heat sink for the semiconductor light devices within the sub-array.

9. The system as recited in claim 1, wherein semiconductor light devices within a sub-array among the one or more sub-arrays have equal aperture sizes.

10. The system as recited in claim 1, wherein the first shape is linear, wherein a first subset of semiconductor light devices within a sub-array among the one or more sub-arrays is arranged on a first row within the sub-array, and wherein a second subset of semiconductor light devices within the sub-array are arranged on a second row within the sub-array.

11. The system as recited in claim 1, further comprising a ground plane substantially surrounding semiconductor light devices within a sub-array among the one or more sub-arrays and forming a coplanar waveguide lead.

12. The system as recited in claim 1, wherein the first shape is linear, wherein the at least one array is arranged horizontally forming a first row, further comprising a plurality of linear arrays arranged horizontally and forming a plurality of rows beneath the first row.

13. The system as recited in claim 1, wherein the first shape is linear, wherein the at least one array is arranged vertically forming a first column, further comprising a plurality of linear arrays arranged vertically and forming a plurality of columns adjoining the first column.

14. The system as recited in claim 1, wherein the plurality of semiconductor light devices are vertical-cavity emitting lasers, further comprising one or more optical elements for converting the first wavelength beam to a frequency doubled wavelength, the one or more optical elements selected from the group comprising of a non-linear crystal, a beam splitter, a polarizing beam splitter, a wavelength filter, a reflector, a lens, a mirror, and an etalon.