32results about How to "Reduce far-field divergence" patented technology

The invention discloses a semiconductor laser. The semiconductor laser comprises a lower-part flat plate waveguide and an upper-part ridge waveguide along a growth direction of an epitaxial layer anda ridge width unchanged region at a back side and a ride width narrowing region at a front side along an optical transmission direction, at the ridge width unchanged region, the ridge width of the upper-part ridge waveguide is maintained unchanged, at the ride width narrowing region, the ridge width of the upper-part ridge waveguide is gradually narrowed, the ridge width of a wide ridge end of theride width narrowing region is equal to the ridge width of the ridge width unchanged region, the ridge width of the ridge end of the ride width narrowing region is smaller than the ridge width of thewide ridge end, a narrow ride end is an optical output end, at the ridge width narrowing region, the equivalent refractive index of the upper-part ridge waveguide is gradually reduced with the ridgewidth gradually narrowed until the narrow ridge end approaches the equivalent refractive index of the lower-part flat plate waveguide, the longitudinal size and the transverse size of a base mode of the narrow ridge both are increased, so that the longitudinal scattering angle and the transverse scattering angle of output light both are reduced. The scattering angle of the output light of the semiconductor laser provided by the invention is smaller than the scattering angle of a conventional ridge waveguide-structure semiconductor laser.

The invention discloses a semiconductor laser and a manufacturing method thereof. The semiconductor laser integrates the first waveguide layer and the second waveguide layer in the passive area by butt-growing in a resonant cavity, and injects current into the active area to generate optical gain. When the lasing is output, it will pass through the double-layer waveguide in the passive area, so that when the light field is coupled to the lower waveguide and reaches the output end face, the vertical size of the spot is effectively increased, the near-field spot is expanded, and the far-field divergence angle is reduced. Therefore, the output quality of the light beam is improved, the adjustment of the light beam is beneficial, the coupling efficiency of the optical fiber is improved, and the coupling cost of packaging is reduced. At the same time, when the light field is transmitted from the double-layer waveguide in the passive area to the single-layer waveguide in the active area, the loss will increase compared with the use of only a single-layer waveguide, thereby increasing the loss of external feedback light, thereby improving the laser’s resistance. reflexes.

The invention discloses a red light semiconductor area array light source device for laser display. The red light semiconductor area array light source device for laser display comprises a VCSEL area array and a microlens array, wherein the VCSEL area array at least comprises a plurality of VCSEL units which are used for emitting circular laser beams, and the microlens array is formed by a plurality of microlens and used for performing collimation rounding on the laser beams output by the VCSEL area array and outputting the laser beams. The light source device can reduce optical elements in a projection display optical path, shorten the length of a lighting optical path, and improve the optical energy utilization rate. In addition, the VCSEL area array can reduce interference between VCSEL lasers and weaken laser speckles, and therefore projection display quality is improved. According to the red light semiconductor area array light source device, the area array light source packaging technology and VCSEL are adopted, a two-dimensional array is easy to integrate, and the defect that power transmitted by a single tube is poor can be overcome. The VCSEL is available in wafer test, reduces cost greatly and is easy in modularization and packaging.

A semiconductor laser and a manufacturing method thereof, comprising the following steps: sequentially growing a buffer layer, a far-field reduction layer, a spacer layer, a quantum well material layer, and a grating layer on a substrate; and etching and removing the grating layer located in the mode spot converter region , make a grating from the grating layer in the laser area; grow a gap layer, an etching stop layer, a cladding layer and a contact layer in turn on the substrate with the grating; use the cladding layer and the contact layer to make an upper ridge waveguide, in which the laser area is The width of the upper ridge waveguide remains unchanged, and the width of the upper ridge waveguide in the mode spot converter area gradually decreases from the laser end to the light-emitting end of the device; after the etching stop layer other than the upper ridge waveguide is removed by selective wet etching, the etching stop layer is Lateral corrosion occurs under the upper ridge waveguide; the lower ridge waveguide is fabricated by etching from the gap layer of the mode spot converter region to the buffer layer. The mode-spot converter integrated on the semiconductor laser of the present invention can be realized by using a common contact photolithography process, which is beneficial to reduce the fabrication cost of the device.

The present invention discloses a ring micro-cavity laser with a directional output. The ring micro-cavity laser comprises an annular micro-cavity resonant cavity, and grating structures are etched and distributed on partial inner wall of the annular resonant cavity. The invention provides the annular semiconductor micro-cavity laser, the far field of output light is controlled through the grating structures distributed on the inner wall of a ring part, thus the small-angle single-direction output can be obtained by a high quality factor mode.