Integrated optoelectronic module
A beam generating device includes a semiconductor substrate, having an optical passband. A first array of vertical-cavity surface-emitting lasers (VCSELs) is formed on a first face of the semiconductor substrate and are configured to emit respective laser beams through the substrate at a wavelength within the passband. A second array of microlenses is formed on a second face of the semiconductor substrate in respective alignment with the VCSELs so as to transmit the laser beams generated by the VCSELs.
1 . A beam generating device, comprising:
a semiconductor substrate, having an optical passband;
a first array of vertical-cavity surface-emitting lasers (VCSELs), which are formed on a first face of the semiconductor substrate and are configured to emit respective laser beams through the substrate at a wavelength within the passband;
a second array of microlenses, which are formed on a second face of the semiconductor substrate, opposite the first face, in alignment with respective ones of the VCSELs so as to transmit the laser beams generated by the VCSELs; and
a lens positioned to receive and transmit the laser beams output from the second array of microlenses,
wherein at least some of the microlenses in the second array are offset along the second face of the semiconductor substrate by different, respective offsets relative to the respective ones of the VCSELs so as to cause the respective laser beams to be transmitted toward the lens at different respective angles.
2 . The device according to claim 1 , wherein the at least some of the microlenses are offset inwardly relative to the VCSELs, so as to cause the respective laser beams to converge together.
3 . The device according to claim 1 , wherein the at least some of the microlenses are offset outwardly relative to the VCSELs, so as to cause the respective laser beams to spread apart.
4 . The device according to claim 1 , wherein the microlenses are configured so that the laser beams are divergent following transmission of the laser beams through the microlenses.
5 . The device according to claim 1 , wherein the microlenses are configured so that the laser beams converge to respective waists following transmission of the laser beams through the microlenses.
6 . The device according to claim 1 , wherein the substrate comprises gallium arsenide.
7 . The device according to claim 1 , wherein the semiconductor substrate is transparent to wavelengths longer than 900 nm.
8 . The device according to claim 1 , wherein the VCSELs are coupled to be driven in predefined groups, so as to vary a diameter of an output beam transmitted by the lens.
9 . The device according to claim 1 , wherein the first and second arrays are configured in a hexagonal arrangement.
10 . A method for producing a beam generating device, comprising:
forming a first array of vertical-cavity surface-emitting lasers (VCSELs) on a first face of a semiconductor substrate so that the VCSELs emit respective laser beams through the substrate at a wavelength within an optical passband of the substrate;
forming a second array of microlenses on a second face of the semiconductor substrate, opposite the first face, in alignment with respective ones of the VCSELs so as to transmit the laser beams generated by the VCSELs; and
positioning a lens to receive and transmit the laser beams output from the second array of microlenses,
wherein forming the second array comprises offsetting at least some of the microlenses in the second array along the second face of the semiconductor substrate by different, respective offsets relative to the respective ones of the VCSELs so as to cause the respective laser beams to be transmitted toward the lens at different respective angles.
11 . The method according to claim 10 , wherein the at least some of the microlenses are offset inwardly relative to the VOSELs, so as to cause the respective laser beams to converge together.
12 . The method according to claim 10 , wherein the at least some of the microlenses are offset outwardly relative to the VOSELs, so as to cause the respective laser beams to spread apart.
13 . The method according to claim 10 , wherein forming the second array comprises configuring the microlenses so that the laser beams are divergent following transmission of the laser beams through the microlenses.
14 . The method according to claim 10 , wherein forming the second array comprises configuring the microlenses so that the laser beams converge to respective waists following transmission of the laser beams through the microlenses.
15 . The method according to claim 10 , wherein the substrate comprises gallium arsenide.
16 . The method according to claim 10 , wherein the semiconductor substrate is transparent to wavelengths longer than 900 nm.
17 . The method according to claim 10 , and comprising coupling the VCSELs to be driven in predefined groups, so as to vary a diameter of an output beam transmitted by the lens.
18 . The method according to claim 10 , wherein the first and second arrays are configured in a hexagonal arrangement.