4results about How to "Increased Laser Damage Threshold" patented technology

The present application relates to optical film and its preparation method and application. The optical film comprises a substrate, a dielectric film and a nanostructure surface layer arranged in sequence, the material of the nanostructure surface layer is selected from fluorine-containing resin or nano-organic silicon, and the porosity of the nanostructure surface layer is 20%-91%; wherein the surface of the nanostructure surface layer away from the substrate has a concave-convex structure, in the convex part of the concave-convex structure, the maximum width of the bottom part close to the substrate is L1, the maximum width of the top part away from the substrate is L2, the height of the convex part is H, 1.1:1≤L1 / L2≤15:1, 1.5:1≤H / L1≤20:1. The optical film has wide spectrum, low reflectivity, low scattering and high laser damage threshold, and can effectively improve the shooting definition and laser damage resistance effect when used in optical devices.

The application belongs to the technical field of inorganic nonlinear optical materials, and particularly discloses a bismuth-based infrared nonlinear optical crystal, a preparation method and application thereof. The molecular formula of the optical crystal is RbBiP2S6, and the crystal structure belongs to a monoclinic system and a space group P21. The optical crystal has excellent second-order nonlinear optical properties, can realize phase matching in an infrared waveband, has a wide light transmission range, and has strong infrared frequency doubling response. The powder frequency doubling intensity of the optical crystal can reach 10-15 times of that of a commercial material AgGaS2, and the laser damage threshold of the optical crystal is 9-13 times of that of an AgGaS2 crystal. The optical crystal has important application value in high-tech fields such as laser frequency conversion, near-infrared probe and photorefractive information processing, and is particularly used for infrared detectors and infrared lasers.

The embodiment of the invention discloses a multi-node structure light field generation device with interactive network characteristics, which comprises a transparent substrate and a plurality of diffraction modulation units, the diffraction modulation units are at least three sheet-shaped fork-shaped gratings, and the number of the sheet-shaped fork-shaped gratings is larger than that of the transparent substrate. The sheet-shaped fork-shaped gratings are integrally inscribed on the surface of the transparent substrate through a laser direct writing technology, each sheet-shaped fork-shaped grating has an independent light field phase modulation function, and from the sheet-shaped fork-shaped grating inscribed for the first time, each sheet-shaped fork-shaped grating has an independent light field phase modulation function relative to the adjacent lower sheet-shaped fork-shaped grating from bottom to top; the sheet-shaped fork-shaped gratings rotate around a shaft in the same direction to generate a constant dislocation angle, the dislocation angle refers to the relative rotation angle between two adjacent sheet-shaped fork-shaped gratings, and the product of the number of the sheet-shaped fork-shaped gratings and the dislocation angle is smaller than or equal to 360 degrees. And the types and complexity of the generated light field are enriched.

A method for surface shape control of optical elements based on target-substrate eccentric deposition includes the following steps: First, select the coating material for the surface shape control layer, calculate the non-uniformity of the film thickness distribution of the coating material under different target-substrate eccentric angles, and determine the actual target-substrate eccentric angle for preparing the surface shape control layer; next, fit the calculated film thickness distribution of the surface shape control layer under the target-substrate eccentric angle to obtain the compensated surface shape power value achieved by the surface shape control layer within a certain deposition time; then, determine the actual deposition time for preparing the surface shape control layer based on the power value to be compensated for the optical element; finally, prepare the surface shape control layer using magnetron sputtering technology. This invention achieves surface shape control by adjusting the relative eccentricity angle between the target and the substrate during magnetron sputtering deposition, adapting to any surface shape optical element without modifying hardware and without affecting the element's optical performance; the thickness of the surface shape control layer is significantly reduced compared to traditional methods, which helps to improve the damage threshold of laser thin film elements.