20 results about "Astigmatism correction" patented technology

The invention relates to the technical field of optical fiber device manufacturing, and discloses a femtosecond laser inscribing low-polarization-dependent-loss optical fiber grating method and system, and the method comprises the steps: firstly, synthesizing an initial phase comprising a flat-topped beam phase, an astigmatism correction phase and a defocus phase, and loading the initial phase to a spatial light phase modulator; therefore, a preset circular flat-top focusing light spot is generated. Secondly, collecting a three-dimensional light field image sequence of a focusing light spot in a low-power detection mode, reconstructing light intensity distribution, extracting effective focal depth and ovality characteristic parameters, dynamically optimizing a phase through a closed-loop feedback mechanism until light field characteristics reach a preset target, and obtaining an optimized phase; and finally, loading an optimized phase in a high-power inscribing mode, and controlling the axial scanning of the optical fiber to inscribe the grating. Accurate active regulation and control of the three-dimensional shape of the focused light field and closed-loop self-optimization of process parameters are realized, birefringence caused by anisotropy of a refractive index modulation area is inhibited from a physical mechanism, and polarization dependent loss of the fiber bragg grating is fundamentally reduced.

The invention discloses an astigmatism coaxial decomposition method, system and device for analyzing the astigmatism correction effect of a corneal refractive surgery, and relates to the technical field of corneal refractive surgeries, and the method comprises the steps: obtaining a preoperative subjective optometry result and a postoperative subjective optometry result of a to-be-evaluated user; based on the preoperative subjective optometry result and the postoperative subjective optometry result, the actual correction refractive power decomposed in the axial direction of the expected correction lenticular lens is determined; based on the preoperative subjective optometry result and the postoperative subjective optometry result, the maximum actual correction refractive power decomposed in the direction perpendicular to the axial direction of the expected correction lenticular lens is determined; the surgical actual corrective diopter of the user is determined based on the actual corrective power decomposed in the axial direction of the lenticular and the maximum actual corrective power decomposed perpendicular to the axial direction of the lenticular. According to the astigmatism description method provided by the invention, the efficiency, practicability and comprehensiveness of astigmatism correction effect analysis are improved.

The invention discloses an imaging parameter correction method capable of automatic focusing and astigmatism correction based on deep learning. The imaging parameter correction method comprises the following steps: acquiring an image as a reference image under a current imaging parameter set; positive increment and negative increment are applied to one or more imaging parameters in the current imaging parameter set to obtain a positive disturbance parameter set and a negative disturbance parameter set, and images are collected under the positive disturbance parameter set and the negative disturbance parameter set respectively to serve as a positive disturbance image and a negative disturbance image; respectively calculating difference images between the positive disturbance image and the reference image and between the negative disturbance image and the reference image; obtaining a prediction parameter adjustment amount by using an imaging parameter correction model based on the difference image; and adjusting the current imaging parameter set according to the predicted parameter adjustment amount. The difference image between the positive disturbance image and the reference image and the difference image between the negative disturbance image and the reference image are provided for the model to carry out adjustment amount prediction, so that the adjustment direction information of imaging parameters is effectively extracted, and the robustness under the condition of a low signal-to-noise ratio is enhanced.

Anamorphic lens assembly having first and second anamorphic lens components, each having an astigmatism at infinity focus that is greater than an astigmatism at close focus. As the anamorphic lens assembly transitions from infinity focus to close focus, the astigmatism decreases for both of the first and second anamorphic lens components, which allows for proper focusing at close focus (when the object is close to the lens assembly). The astigmatism of the first anamorphic lens component may be equal and opposite to the astigmatism of the second anamorphic lens component, such that the astigmatisms of the anamorphic lens components cancel out one another.

Sample regions of interest (ROIs) for use in autofocus procedures are identified based on a gradient image of the sample. ROIs with gradient values greater that a threshold are selected, and eigenvalues of the associated image matrices are determined. ROIs with suitable variation in eigenvalues such as at least two relatively large eigenvalues are associated with high contrast features orientated in multiple directions so that such ROIs are suitable for automatic focus and astigmatism correction. Suitable ROIs can also be identified based on a histogram of gradient orientations.

The invention discloses a fixed-axis contact lens capable of preventing highlight patterns from rotating. The fixed-axis contact lens comprises an optical area located in the center, a balance area arranged around the optical area, auxiliary supporting areas symmetrically arranged on the left side and the right side below the balance area, a thinning area arranged above the balance area and a vertical weight area arranged below the auxiliary supporting areas. Transition buffer areas are arranged on the peripheries of the thinning area, the auxiliary supporting area and the vertical weight area, and edge areas are arranged on the peripheries of the transition buffer areas. According to the invention, the thinning area and the vertical weight area are oppositely arranged in the vertical direction, and the asymmetric thickness structure of the auxiliary supporting area is combined, so that a vertical and horizontal two-dimensional anti-rotation locking mechanism is formed, the angle deviation of the highlight pattern can be controlled within + / -1 degree, and meanwhile, the oxygen permeation rate and the wearing comfort are ensured; the contact lens is suitable for highlight decoration and astigmatism correction.

The invention discloses an astigmatism correction type asymmetric peripheral defocusing corneal contact lens which comprises an optical correction area, a peripheral defocusing area, a transition area, an off-axis positioning area and an astigmatism axis position mark. The optical correction area provides optical imaging and astigmatism correction; the peripheral defocusing area provides asymmetric peripheral defocusing to realize hyperopia asymmetric defocusing of the marginal area of the retina; the transition area is a transition area between the outside of the peripheral defocusing area and the positioning area; the upper side and the lower side of the off-axis positioning area are different in thickness and are used for wearing and positioning the contact lens; different areas of the corneal contact lens are designed, an enforceable algorithm is provided, the optical correction area provides correction of astigmatism ametropia, the peripheral defocus area provides asymmetric hyperopia defocus, hyperopia asymmetric defocus of the marginal area of the retina is achieved, and the optical correction area and the peripheral defocus area are integrated into the corneal contact lens. The upper side and the lower side of the off-axis positioning area are different in thickness, and the off-axis positioning design of ergonomics is better met.

This invention discloses a high-transmittance adaptive focusing liquid crystal lens structure and standardized preparation method supporting polymer nanotransmission, belonging to the field of intelligent wearable optical devices and nanomaterial transmission technology. The lens adopts a four-layer integrated stacked structure consisting of a wear-resistant and anti-fouling blue light blocking protective layer, a polarization-independent gradient refractive index liquid crystal focusing layer, a nano-metasurface polarization conversion layer, and a high-transmittance substrate layer. A carbon nanotube-graphene-polyimide composite polymer nanotransmission interface is integrated at the edge. Through a precise 45°±0.3° angle between the metasurface layer and the liquid crystal molecule director and a bipolar polarizer composite liquid crystal design, it achieves a transmittance ≥82%, polarization independence ΔT ≤3.2%, focusing response ≤180ms, steady-state error ≤±0.10D, and nanotransmission loss ≤3% under polarizer-free conditions. It can be adapted to -10.00D to +6.00D myopia / hyperopia and ±6.00D astigmatism correction. This invention features a standardized six-step mass production process, with a single-piece manufacturing time of ≤90 minutes and a yield of ≥95%, completely solving common industry pain points such as low light transmittance, polarization dependence, high transmission loss, inconsistent processes, and difficulty in large-scale mass production of traditional liquid crystal lenses. This invention boasts an original structure, novel process, and performance comprehensively superior to similar international technologies, possessing extremely high patent licensing value and industrial mass production value.

This invention discloses a miniaturized, all-electrostatic scanning electron microscope (SEM) lens suitable for in-situ lunar surface exploration, belonging to the field of lunar exploration technology. It includes: an electron gun, a condenser lens module, a microchannel plate detector, and an objective lens system, all fixed sequentially along the axis. The lens employs an all-electrostatic system, with through-holes in the condenser lens module and objective lens system to introduce the natural vacuum environment of the lunar surface. The condenser lens module features an innovative multi-functional electrode structure, enabling the condenser to also function as an aperture stop. The objective lens system integrates an electrostatic deflector capable of simultaneously performing scanning deflection and astigmatism correction. This invention, through its all-electrostatic design, integrated and compact design for introducing lunar surface vacuum, effectively overcomes the magnetic leakage and heat loss of traditional electromagnetic lenses, reduces reliance on complex vacuum equipment, improves system integration, and meets the requirements for miniaturization and lightweight lunar surface exploration payloads. It also enhances the structural reliability of the system under launch vibration and lunar seismic environments.

Anamorphic lens assembly having first and second anamorphic lens components, each having an astigmatism at infinity focus that is greater than an astigmatism at close focus. As the anamorphic lens assembly transitions from infinity focus to close focus, the astigmatism decreases for both of the first and second anamorphic lens components, which allows for proper focusing at close focus (when the object is close to the lens assembly). The astigmatism of the first anamorphic lens component may be equal and opposite to the astigmatism of the second anamorphic lens component, such that the astigmatisms of the anamorphic lens components cancel out one another.

The invention relates to a large-depth-of-field astigmatism correction type implantable contact lens based on a photoetching technology and a preparation method, and belongs to the technical field of ophthalmology implantation instruments. The optical area of the contact lens comprises a central functional area and a peripheral adaptive area; the diameter of the central functional area is 1.2 mm, and a 32-order continuous curvature gradient structure is formed by processing through a deep ultraviolet curved surface photoetching technology; the curvature change range is 7.0 mm to 7.8 mm. Smooth transition without optical abrupt change is achieved between the 32-order curvature transition area of the central functional area and the peripheral adaptive area through a 0.2 mm wide transition curvature section. A sub-wavelength polarization regulation grating is arranged in the peripheral adaptation area, the grating is formed through the photoetching-ion beam etching technology and is of a rectangular tooth-shaped structure, the grating period is 300-500 nm, the depth is 0.12 m + / -0.02 m, and the included angle between the grating line direction and the optical center axis is 45 degrees. According to the invention, the night glare rate can be greatly reduced, the detail resolution under the medium-high spatial frequency is improved by more than 30% compared with the existing product, and the processing technology can greatly improve the yield.

The invention provides a free-form surface astigmatism lens design method based on differentiable ray tracing, is used for astigmatism correction of specific axial positions of human eyes, and belongs to the field of eye vision optical design. Design of the free-form surface lens is realized through a differentiable ray tracing technology, the method fuses multi-lens-eye distance simulation to comprehensively evaluate aberration, constraints of edge thickness and surface curvature inflection points are synchronously introduced in an optimization process, and optimization iteration of a free-form surface system is driven by gradient calculation of lens parameters by means of an evaluation function. And finally, focal power matching in different view fields is realized through the high degree of freedom of the curved surface, so that personalized astigmatism correction requirements of specific axial positions of human eyes are met, the method is suitable for design and manufacturing of astigmatism correction lenses, and the astigmatism correction effect can be improved compared with design of traditional spherical cylinders and the like.

An apparatus may include a viewing optic. The viewing optic may include a first rotatable phase plate, a second rotatable phase plate, and an adjustable focus device. The viewing optic may be configured to image light from a display, the imaged light having a spherical power, a cylindrical power, and a cylindrical axis. The spherical power, the cylindrical power, and the cylindrical axis of the imaged light may be controlled by adjusting the adjustable focus device, rotating the first rotatable phase plate, and rotating the second rotatable phase plate. Other devices, apparatuses, systems, and methods of manufacture are also disclosed.

An ophthalmic apparatus includes an interference optical system, an optical scanner controller, and a correction controller. The interference optical system includes an astigmatism correction optical member and an optical scanner, and is configured to split light from a light source into reference light and measurement light, irradiate the measurement light onto the subject's eye via the astigmatism correction optical member and the optical scanner, and detect interference light between returning light of the measurement light and the reference light. The optical scanner controller is configured to control the optical scanner so as to deflect the measurement light in a horizontal direction and a vertical direction on a plane perpendicular to an optical axis of the interference optical system. The correction controller is configured to control the astigmatism correction optical member so as to correct astigmatism based on a detection result of the interference light obtained by the interference optical system.

This application relates to ophthalmic lenses for use in the eye. The ophthalmic lens includes an anterior surface, a posterior surface, an optical center, and an optical region surrounding the optical center. The optical region includes a basic prescription for the eye and multiple non-refractive features; wherein the basic prescription includes spherical correction, astigmatism correction, or spherical and astigmatism correction. The non-refractive features contribute to increased retinal ganglion cell activity in the wearer, which can serve as an optical stopping signal to slow, improve, control, inhibit, or reduce the rate of myopia progression in the wearer.

The invention relates to the technical field of electrowetting cylindrical lens optical systems, and discloses an astigmatism correction and imaging optimization method for an electrowetting cylindrical lens optical system, and the method comprises the steps: obtaining the structure parameters and imaging environment parameters of the electrowetting cylindrical lens optical system, and determining a target imaging state; generating voltage driving signals including voltage amplitude, phase difference and driving frequency based on an astigmatism correction model, and performing real-time regulation and control on the electrowetting cylindrical lens; a self-adaptive optical compensation structure is adopted to adjust the system in real time, and axial and radial astigmatism errors are effectively corrected; the system monitors an imaging quality index in real time, and adjusts parameters of a voltage driving signal when detecting that the system deviates from a target state, such as adjusting voltage amplitude, phase difference or driving frequency, so as to realize adaptive astigmatism correction and imaging quality optimization. The astigmatism correction capability and the imaging stability of the electrowetting cylindrical lens optical system are effectively improved.

Provided are an astigmatism correction method of an electron beam imaging device, a product and an apparatus. The astigmatism correction method includes: searching a target astigmatism parameter of a stigmator in the electron beam imaging device; gradually adjusting a preadjustment objective lens current according to a set step size, and collecting a plurality of fine focused images corresponding to different objective lens currents; calculating gradients of the plurality of fine focused images in different coordinate axis directions; judging whether the target astigmatism parameter meets an astigmatism correction requirement according to consistency of the gradients; and if yes, determining a target objective lens current of the electron beam imaging device according to the gradients. Astigmatism correction accuracy is improved, and the problem that measurement accuracy is low due to application of an error astigmatism correction result is avoided, thereby improving the measurement accuracy of the electron beam imaging device.

Systems and methods for variable astigmatism correction in a head mounted display are disclosed. An apparatus may include viewing optics. The viewing optics may include a first rotatable phase plate, a second rotatable phase plate, and an adjustable focus device. The viewing optics may be configured to image light from the display, the imaged light having a spherical power, a cylindrical power, and a cylindrical axis. The spherical focal power, the cylindrical focal power and the cylindrical axis of the imaging light can be controlled by adjusting the adjustable focal length device, rotating the first rotatable phase plate and rotating the second rotatable phase plate. Other apparatus, devices, systems, and methods of manufacture are also disclosed.

An ophthalmic apparatus includes an interference optical system, an optical scanner controller, and a correction controller. The interference optical system includes an astigmatism correction optical member and an optical scanner, and is configured to split light from a light source into reference light and measurement light, to irradiate the measurement light onto the subject's eye via the astigmatism correction optical member and the optical scanner, and to detect interference light between returning light of the measurement light from the subject's eye and the reference light. The optical scanner controller is configured to control the optical scanner so as to deflect the measurement light in a horizontal direction and a vertical direction on a plane perpendicular to an optical axis of the interference optical system. The correction controller is configured to control the astigmatism correction optical member so as to correct astigmatism based on a detection result of the interference light obtained by the interference optical system.

This invention relates to the field of progressive multifocal lens (PAL) design and manufacturing technology, specifically disclosing a method and system for designing freeform surfaces of progressive multifocal lenses. This method employs a curvature superposition (CS) algorithm instead of the traditional differential geometry (DG) algorithm, resulting in better consistency between the spherical power distribution and the design values. Based on this, a fast Fourier transform (FFT) is used to optimize the initial freeform surface, effectively reducing unwanted astigmatism and expanding the progressive corridor width, significantly enhancing visual function and wearing comfort. The manufactured product successfully replicates the simulated optical performance and maintains optimized characteristics even when combined with standard cylindrical astigmatism correction, proving the method's practicality and feasibility. This design method, combining the CS algorithm and FFT filtering, effectively improves the optical performance and wearing comfort of PAL, providing a new path for PAL design and optimization.