7 results about "Refractive index dispersion" patented technology

The invention relates to a doped TiO2 metasurface integrated optical system. The simulation modeling doping subsystem is used for realizing material directional design through preposed atomic-scale precise simulation, simulating and driving a modified titanium dioxide material to optimize a doping system, and outputting a refractive index dispersion curve and an extinction coefficient curve of a full visible light wave band; the metasurface integration subsystem selectively transmits a set phase incident ray in an original optical ray based on light polarization, and realizes the integration effect of multiple types of functions of polarization conversion, polarization selective reflection and aberration correction through three-dimensional parameter cooperation; dynamic compensation polarization crosstalk and phase deviation are complementary with static regulation and control, residual stray light is filtered, high-contrast vertical-direction linearly polarized light imaging is formed, and a complete optical system is formed; a system light path follows a light path complete process of polarization screening, integrated regulation and control, dynamic compensation and purification; the characteristics of high imaging quality and low loss are kept in a wide view field range; and the light path control precision and accuracy are improved.

This invention discloses an online precision measurement method for the thickness of ultrathin multilayer co-extruded release films, belonging to the field of online multilayer film thickness detection technology. The method includes: acquiring the original spectral interference signal set of the online-running ultrathin multilayer co-extruded release film at multiple consecutive sampling times; performing frequency domain transformation processing on the original spectral interference signal set based on an improved Fourier transform algorithm, where the improved Fourier transform algorithm corrects the kernel function of the traditional Fourier transform based on the nonlinear relationship between the refractive index of the film material and wavelength, obtaining a frequency domain characteristic sequence of film thickness; and analyzing the total thickness value and the partial thickness values ​​of each sublayer based on the position distribution of each frequency peak in the frequency domain characteristic sequence of film thickness, generating an initial measurement result of the thickness distribution. This invention eliminates the influence of refractive index dispersion by correcting the Fourier transform kernel function and improves the analytical accuracy of multilayer film thickness through subsequent interlayer crosstalk correction.

This invention belongs to the field of optical material measurement technology, specifically a device and method for measuring the refractive index of curved optical lenses based on white light spectral interferometry. The invention employs a Michelson interferometer combined with a small-core fiber optic detection scheme. A 45-degree mirror folds the optical path vertically, allowing the curved lens sample to be placed horizontally on a sample holder. The small-core fiber collects interference signals only from the central region of the lens, enabling the curved interference to be approximated by an equivalent planar model. During measurement, the interference spectrum of the sample in place and the air reference spectrum after sample removal are collected separately. The group refractive index dispersion curve of the sample over a wide wavelength range is calculated by analyzing the fringe period. This invention eliminates the need for a flat sample, allowing direct measurement of curved lenses and spectacle lenses; it also eliminates the need for mechanical scanning components, offering a wide measurement range and high accuracy.

The present application relates to the technical field of thickness detection, and particularly relates to a thickness uniformity detection method for VCSEL epitaxial wafer production. The method acquires a reference reflectance spectrum of a detection point of a VCSEL epitaxial wafer; acquires an interference degree according to the distribution characteristics of a reference layer and a resonant cavity layer; acquires a theoretical reflectance spectrum based on the preset thickness of each layer of the VCSEL epitaxial wafer and the refractive index dispersion relationship; acquires a deviation degree according to the difference in reflectance intensity between the theoretical reflectance spectrum and the reference reflectance spectrum and the interference degree; adjusts the preset thickness to acquire the corresponding deviation degree after each adjustment until the deviation degree meets a stop condition; and takes the preset thickness of the resonant cavity layer in the final adjustment as the reference thickness of the detection point to detect the thickness uniformity of the VCSEL epitaxial wafer production. The present application accurately acquires the reference thickness of each detection point, effectively improving the accuracy of the analysis of the thickness uniformity of the VCSEL epitaxial wafer.

The invention relates to the technical field of thickness detection, in particular to a thickness uniformity detection method for VCSEL epitaxial wafer production. The method comprises the following steps: acquiring a reference reflection spectrum chart of a VCSEL epitaxial wafer detection point; obtaining the interference degree according to the distribution characteristics of the reference layer and the resonant cavity layer; obtaining a theoretical reflection spectrogram based on the preset thickness of each layer of the VCSEL epitaxial wafer and the refractive index dispersion relation; obtaining a deviation degree according to a reflection intensity difference and an interference degree in the theoretical reflection spectrum chart and the reference reflection spectrum chart; and adjusting the preset thickness, obtaining the corresponding deviation degree after each adjustment until the deviation degree meets a stop condition, and detecting the thickness uniformity of the VCSEL epitaxial wafer production by taking the preset thickness corresponding to the resonant cavity layer in the final adjustment as the reference thickness of the detection point. According to the VCSEL epitaxial wafer thickness uniformity analysis method, the reference thickness of each detection point is accurately obtained, so that the accuracy of VCSEL epitaxial wafer thickness uniformity analysis is effectively improved.

The application provides a semiconductor laser element with an interlayer hot exciton conversion layer, and relates to the technical field of semiconductor optoelectronic devices, which comprises, from bottom to top, a substrate, a lower confinement layer, a lower waveguide layer, an active layer, an upper waveguide layer, an electron blocking layer, and an upper confinement layer; an interlayer hot exciton conversion layer is arranged between the upper confinement layer and the electron blocking layer and between the lower confinement layer and the lower waveguide layer; in the charge transport process of the laser element, the interlayer hot exciton conversion layer forms a mismatched momentum, generates a large number of interlayer hot excitons, and is converted into a tightly bound interlayer exciton after the release of extra energy, thereby improving the peak gain of the active layer of the laser element and improving thermal degradation, reducing non-radiative recombination centers, improving the refractive index dispersion of the laser element, improving the confinement factor of the laser element, improving the mode gain, improving the radiation recombination efficiency of the active layer of the laser element, reducing the excitation threshold of the laser element, and improving the optical power and the slope efficiency of the laser element.

This invention proposes a semiconductor laser with a biexciton quantum confinement layer, comprising, from bottom to top, a substrate, a lower confinement layer, a lower waveguide layer, an active layer, an upper waveguide layer, an electron blocking layer, and an upper confinement layer. The lower waveguide layer, the active layer, and the upper waveguide layer constitute the biexciton quantum confinement layer. The thickness of the well layer in the active layer is greater than the thickness of the barrier layer. The Si doping concentration and In content of the biexciton quantum confinement layer both reach their peak values ​​in the active layer. This invention can reduce In segregation in the active layer, improve In composition fluctuations, reduce valence band junction, enhance hole injection and hole transport efficiency, make the electron wavefunction amplitude of the active layer smaller than the Bohr exciton radius, limit low refractive index dispersion, generate quantum confinement effect and biexciton optical gain, enhance quantum state splitting and suppress Auger decay, enhance biexciton emission efficiency, thereby reducing the laser threshold, extending the laser gain lifetime, and increasing laser power.