System and Method of Multi-Wavelength Laser Apparatus
A system and method for providing laser diodes emitting multiple wavelengths is described. Multiple wavelengths and/or colors of laser output are obtained by having multiple laser devices, each emitting a different wavelength, packaged onto the same substrate. In other embodiments, multiple laser devices having different wavelengths are formed from the same substrate.
1 . An optical device comprising:
a gallium and nitrogen containing substrate including a first crystalline surface region of semi-polar or non-polar orientation;
an active region comprising a barrier layer and a light emission layer, the light emission layer being characterized by a graduated profile associated with a peak emission wavelength gradient, the peak emission wavelength gradient having a deviation of at least 10 nm;
a first cavity member overlaying a first portion of the emission layer, the first portion of the emission layer being associated with a first wavelength, the first cavity member being characterized by a length of at least 100 um and a width of at least 0.5 um, the first cavity member being adapted to emit a first laser beam at the first wavelength;
a second cavity member overlaying a second portion of the emission layer, the second portion of the emission layer being associated with a second wavelength, a difference between the first and second wavelengths being at least 50 nm, the second cavity member being characterized by a length of at least 100 um and a width of at least 0.5 um, the second cavity member being adapted to emit a second laser beam at a second wavelength; and
an output region.
2 . The device of claim 1 wherein:
the first wavelength is associated with a green color;
the second wavelength is associated with a blue color.
3 . The device of claim 1 further comprising a plurality of metal electrodes for selectively exciting the active region.
4 . The device of claim 1 wherein the active region comprises at least four quantum well regions.
5 . The device of claim 1 wherein the active region is configured operably for a forward voltage of <7V for an output power of 60 mW and greater.
6 . An optical device comprising:
a back member having a first surface;
a first substrate mounted on the first surface of the back member, the first substrate comprising a gallium and nitrogen material, the first substrate having a first crystalline surface region orientation, the first crystalline surface orientation being semi-polar or non-polar;
a first active region comprising a first barrier layer and a first light emission layer, the first light emission layer being associated with a first wavelength;
a second substrate mounted on the first surface of the back member, the first substrate having a second crystalline surface region orientation;
a second active region comprising a second barrier layer and a second light emission layer, the second light emission layer being associated with a second wavelength, a difference between the first and second wavelengths being at least 10 nm;
a first cavity member overlaying the first light emission layer, the first cavity member being characterized by a length of at least 100 um and a width of at least 0.5 um, the first cavity member having a first surface, the first cavity member being adapted to emit a first laser beam at the first wavelength;
a second cavity member overlaying a second light emission layer, the second cavity member being characterized by a length of at least 100 um and a width of at least 0.5 um, the second cavity member having a second surface, the first and second surfaces being substantially parallel, the second cavity member being adapted to emit a second laser beam at a second wavelength; and
an output region.
7 . The device of claim 6 wherein the first wavelength is about 420 nm to 490 nm and the second wavelength is about 490 nm to 560 nm.
8 . The device of claim 6 further comprising:
a third substrate mounted on the first surface of the back member, the third substrate having a third crystalline surface region orientation;
a third active region comprising a third barrier layer and a third light emission layer, the third light emission layer being associated with a third wavelength;
a third cavity member overlaying the third light emission layer, the third cavity member being characterized by a length of at least 100 um and a width of at least 0.5 um, the second cavity member having a third surface, the first and third surfaces being substantially parallel, the third cavity member being adapted to emit a third laser beam at a third wavelength.
9 . The device of claim 6 wherein the first crystalline surface region orientation is polar, non-polar, or semi-polar.
10 . The device of claim 6 wherein the first crystalline surface region orientation is semi-polar and the first wavelength is characterized by a green color.
11 . The device of claim 6 wherein the first crystalline surface region orientation is on the c-plane and the first wavelength is characterized by a blue color.
12 . The device of claim 6 wherein:
the first light emitting layer comprises AlInGaP material;
the first wavelength is characterized by a red color;
the second crystalline surface region orientation is semi-polar;
the second wavelength is characterized by a green color.
13 . The device of claim 6 further comprising a plurality of optics having dichroic coatings for combining the first and the second laser beams.
14 . The device of claim 6 further comprising a plurality of polarizing optics for combining the first and the second laser beams.
15 . The device of claim 6 further comprising an optical member for combining the first and second laser beams at the output region.
16 . The device of claim 6 wherein first crystalline surface region orientation is a {20-21} plane or {30-31} plane.
17 . An optical device comprising:
a first submount;
a second submount having a first top surface and a first bottom surface, the first bottom surface being coupled to the first submount;
a third submount having a second top surface and a second bottom surface, the second bottom surface being coupled to the first submount, the third submount being separated from the second submount;
a first substrate mounted on the first top surface, the first substrate comprising a gallium and nitrogen material, the first substrate having a first crystalline surface region orientation, the first crystalline surface orientation being semi-polar or non-polar, the first substrate comprising a first barrier layer and a first light emission layer, the first light emission layer being associated with a first wavelength;
a first cavity member overlaying the first light emission layer, the first cavity member being characterized by a length of at least 100 um and a width of at least 0.5 um, the first cavity member having a first surface, the first cavity member being adapted to emit a first laser beam at the first wavelength;
a second substrate mounted on the second top surface;
a second cavity member overlaying the second substrate, the second cavity member being associated with a second wavelength.
18 . The device of claim 17 wherein the first substrate second substrate is characterized by a polar orientation.
19 . The device of claim 17 further comprising a third cavity member overlaying the first substrate, the third cavity member being associated with a third wavelength different from the first wavelength.
20 . The device of claim 17 further comprising a third substrate mounted on the first top surface, the third substrate being separated from the first substrate, the third substrate being associated with a semipolar or non-polar orientation.
21 . The device of claim 17 further comprising:
a third submount, the third substrate being separate from the first submount and the second submount;
a third substrate mounted on the third submount;
a third cavity member overlaying the third substrate.