Abstract: A semiconductor layer structure may include a substrate, a blocking layer disposed over the substrate, and one or more epitaxial layers disposed over the blocking layer. The blocking layer may have a thickness of between 50 nanometers (nm) and 4000 nm. The blocking layer may be configured to suppress defects from the substrate propagating to the one or more epitaxial layers. The one or more epitaxial layers may include a quantum-well layer that includes a quantum-well intermixing region formed using a high temperature treatment.

Abstract: In some implementations, a microruler is patterned on a surface of a wafer to enable visual overspray screening and/or quantitative measurement. For example, a laser bar cleaved from a wafer may comprise multiple laser devices that each include a first facet and a second facet, an anti-reflective (AR) coating applied to the first facet, and a highly reflective (HR) coating applied to the second facet. Furthermore, a set of microrulers may be patterned on a surface of the laser bar, where each microruler in the set of microrulers is aligned with a bar cleaving line where the laser bar was cleaved from the wafer, and each microruler has multiple graduation markings that each represent a respective distance from the bar cleaving line such that the graduation markings can be used to quantitatively measure an overspray of the AR coating or the HR coating relative to the bar cleaving line.

Abstract: A semiconductor layer structure may include a substrate, a blocking layer disposed over the substrate, and one or more epitaxial layers disposed over the blocking layer. The blocking layer may have a thickness of between 50 nanometers (nm) and 4000 nm. The blocking layer may be configured to suppress defects from the substrate propagating to the one or more epitaxial layers. The one or more epitaxial layers may include a quantum-well layer that includes a quantum-well intermixing region formed using a high temperature treatment.

Abstract: A zoned waveplate has a series of transversely stacked birefringent zones alternating with non-birefringent zones. The birefringent and non-birefringent zones are integrally formed upon an AR-coated face of a single substrate by patterning the AR coated face of the substrate with zero-order sub-wavelength form-birefringent gratings configured to have a target retardance. The layer structure of the AR coating is designed to provide the target birefringence in the patterned zones and the reflection suppression.

Abstract: A vertical cavity surface emitting laser (VCSEL) array may comprise a first subset of VCSELs of a plurality of VCSELs, and a second subset of VCSELs of the plurality of VCSELs. One or more first beams to be emitted by the first subset of VCSELs, when the VCSEL array is powered, and one or more second beams to be emitted by the second subset of VCSELs, when the VCSEL array is powered, may have different patterns of areas of energy intensity. The different patterns of areas of energy intensity may include respective areas of high energy intensity and respective areas of low energy intensity.

Abstract: A semiconductor layer structure may include a substrate, a blocking layer disposed over the substrate, and one or more epitaxial layers disposed over the blocking layer. The blocking layer may have a thickness of between 50 nanometers (nm) and 4000 nm. The blocking layer may be configured to suppress defects from the substrate propagating to the one or more epitaxial layers. The one or more epitaxial layers may include a quantum-well layer that includes a quantum-well intermixing region formed using a high temperature treatment.

Abstract: A vertical cavity surface emitting laser (VCSEL) array may comprise a first subset of VCSELs of a plurality of VCSELs, and a second subset of VCSELs of the plurality of VCSELs. One or more first beams to be emitted by the first subset of VCSELs, when the VCSEL array is powered, and one or more second beams to be emitted by the second subset of VCSELs, when the VCSEL array is powered, may have different patterns of areas of energy intensity. The different patterns of areas of energy intensity may include respective areas of high energy intensity and respective areas of low energy intensity.

Abstract: A vertical cavity surface emitting laser (VCSEL) array may comprise a first subset of VCSELs of a plurality of VCSELs, and a second subset of VCSELs of the plurality of VCSELs. One or more first beams to be emitted by the first subset of VCSELs, when the VCSEL array is powered, and one or more second beams to be emitted by the second subset of VCSELs, when the VCSEL array is powered, may have different patterns of areas of energy intensity. The different patterns of areas of energy intensity may include respective areas of high energy intensity and respective areas of low energy intensity.

Abstract: A reflective diffraction grating and a fabrication method are provided. The reflective diffraction grating includes a substrate, a UV-absorbing layer, a grating layer having a binary surface-relief pattern formed therein, and a conforming reflective layer. Advantageously, the UV-absorbing layer absorbs light at a UV recording wavelength to minimize reflection thereof by the substrate during holographic patterning at the UV recording wavelength.

Abstract: A zoned waveplate has a series of transversely stacked birefringent zones alternating with non-birefringent zones. The birefringent and non-birefringent zones are integrally formed upon an AR-coated face of a single substrate by patterning the AR coated face of the substrate with zero-order sub-wavelength form-birefringent gratings configured to have a target retardance. The layer structure of the AR coating is designed to provide the target birefringence in the patterned zones and the reflection suppression.

Abstract: A sub-wavelength thin-film metal grating is placed inside a liquid crystal variable optical retarder at a selected distance from a reflective electrode to form a reflective half wave plate, thereby reducing polarization dependence of the optical retardation generated by the variable optical retarder. The approach enables to form within the device the reflective half wave plate that is suitably thin without modifying the reflective electrode of the device.

Abstract: A zoned waveplate has a series of transversely stacked birefringent zones alternating with non-birefringent zones. The birefringent and non-birefringent zones are integrally formed upon an AR-coated face of a single substrate by patterning the AR coated face of the substrate with zero-order sub-wavelength form-birefringent gratings configured to have a target retardance. The layer structure of the AR coating is designed to provide the target birefringence in the patterned zones and the reflection suppression.

Abstract: A vertical cavity surface emitting laser (VCSEL) array may comprise a first subset of VCSELs of a plurality of VCSELs, and a second subset of VCSELs of the plurality of VCSELs. One or more first beams to be emitted by the first subset of VCSELs, when the VCSEL array is powered, and one or more second beams to be emitted by the second subset of VCSELs, when the VCSEL array is powered, may have different patterns of areas of energy intensity. The different patterns of areas of energy intensity may include respective areas of high energy intensity and respective areas of low energy intensity.

Abstract: A zoned waveplate has a series of transversely stacked birefringent zones alternating with non-birefringent zones. The birefringent and non-birefringent zones are integrally formed upon an AR-coated face of a single substrate by patterning the AR coated face of the substrate with zero-order sub-wavelength form-birefringent gratings configured to have a target retardance. The layer structure of the AR coating is designed to provide the target birefringence in the patterned zones and the reflection suppression.

Abstract: A zoned waveplate has a series of transversely stacked birefringent zones alternating with non-birefringent zones. The birefringent and non-birefringent zones are integrally formed upon an AR-coated face of a single substrate by patterning the AR coated face of the substrate with zero-order sub-wavelength form-birefringent gratings configured to have a target retardance. The layer structure of the AR coating is designed to provide the target birefringence in the patterned zones and the reflection suppression.

Abstract: A zoned waveplate has a series of transversely stacked birefringent zones alternating with non-birefringent zones. The birefringent and non-birefringent zones are integrally formed upon an AR-coated face of a single substrate by patterning the AR coated face of the substrate with zero-order sub-wavelength form-birefringent gratings configured to have a target retardance. The layer structure of the AR coating is designed to provide the target birefringence in the patterned zones and the reflection suppression.

Abstract: A reflective diffraction grating and a fabrication method are provided. The reflective diffraction grating includes a substrate, a UV-absorbing layer, a grating layer having a binary surface-relief pattern formed therein, and a conforming reflective layer. Advantageously, the UV-absorbing layer absorbs light at a UV recording wavelength to minimize reflection thereof by the substrate during holographic patterning at the UV recording wavelength.

Abstract: A reflective diffraction grating and a fabrication method are provided. The reflective diffraction grating includes a substrate, a UV-absorbing layer, a grating layer having a binary surface-relief pattern formed therein, and a conforming reflective layer. Advantageously, the UV-absorbing layer absorbs light at a UV recording wavelength to minimize reflection thereof by the substrate during holographic patterning at the UV recording wavelength.

Abstract: A sub-wavelength thin-film metal grating is placed inside a liquid crystal variable optical retarder at a selected distance from a reflective electrode to form a reflective half wave plate, thereby reducing polarization dependence of the optical retardation generated by the variable optical retarder. The approach enables to form within the device the reflective half wave plate that is suitably thin without modifying the reflective electrode of the device.

Abstract: A zoned waveplate has a series of transversely stacked birefringent zones alternating with non-birefringent zones. The birefringent and non-birefringent zones are integrally formed upon an AR-coated face of a single substrate by patterning the AR coated face of the substrate with zero-order sub-wavelength form-birefringent gratings configured to have a target retardance. The layer structure of the AR coating is designed to provide the target birefringence in the patterned zones and the reflection suppression.