53results about How to "Eliminate astigmatism" patented technology

A holographic laser scanners of ultra-compact and modular design capable of reading bar and other types of graphical indicia within a large scanning volume using holographic optical elements and visible laser diodes, and also a method of designing and operating the same for use in diverse applications.

The invention discloses a control device and method for achieving wide-range scanning of an electron beam and a additive manufacturing device capable of achieving the wide-range scanning of the electron beam. The control device comprises a negative electrode, a grid electrode, a positive electrode, a focusing coil, a deflecting coil, an anastigmatic coil and a DA converter, wherein the anastigmatic coil is used for generating anastigmatic magnetism which can produce an anastigmatic magnetic field to control the astigmatic degree. According to the control device, the current of the focusing coil can be changed to achieve good focusing of the electron beam; in addition, the current of the anastigmatic coil can be changed to remove astigmatism of the electron beam, and thus beam spots can remain high quality; in addition, the formation quality of electron beam selective melting additive manufacturing (3D printing) can be greatly improved, and particularly the precision and quality of printed large parts can be improved. The control method is high in operability, and enables high-quality scanning of the electron beam in any route and within a wide range.

The invention provides a method for testing the resolution of each imaging region of a digital camera. A camera to be tested is used for shooting resolution test plates to obtain photos, and the photos are treated according to the following steps: 1. converting into gray level images; 2. calculating the diameters of the photo images; 3. carrying out dark corner light loss correction; 4. carrying out binaryzation on the images; 5. dividing a plurality of pixel blocks to be used as foreground pixel blocks; 6. removing the foreground pixel blocks positioned at edges or corners of the photos or the foreground pixel blocks with too small area; 7. establishing a plurality of concentric circles for dividing the photo images into a plurality of annular regions; and calculating the astigmation of each annular region; and 8. calculating the relative astigmation and the resolution of each annular region in the photo images. The invention can determine the clear usable region of the photos shot by a set of camera equipment, and can also compare the resolution difference in different proportions between the whole shooting picture and the middle cut image, and the shooting method with the maximum resolution can be found, so the required shooting number is minimum on the premise that the resolution in the conversion is maximum or the resolution is ensured.

A holographic laser scanning system for carrying out laser beam scanning operations with improved light collection efficiency. The holographic laser scanning system comprises: a housing of compact construction; a plurality of laser beam sources; a holographic scanning disc supporting a plurality of holographic optical elements having fringe structure of variable spatial frequency; a plurality of laser beam folding mirrors disposed about the holographic scanning disc; a plurality of light focusing surfaces disposed below the holographic scanning disc; and a plurality of photodetectors disposed at the focal points of the light focusing surfaces. During laser beam scanning operations, each laser beam is transmitted through the outer edge portion of each holographic optical element at an angle of incidence. During light collection operations, a portion of the laser light rays reflected off a code symbol scanned by a produced laser scanning plane is collected over the total surface area of the holographic optical element producing the laser scanning plane. The collected laser light rays are focused by the light focusing surface to the respective photodetector, for detecting the intensity of the focused laser light rays for detection and generation of a scan data signal for subsequent processing. By virtue of the system of the present invention, light collection operations are carried out with improved light collection efficiency.

The invention is an IV-type concave holographic grating making process flow, belonging to the field of spectrum technique, relating a grating making process flow. And its technical solution comprises: substrate treatment, coating glue, front drying, holographic exposure, development, after drying, thermal melting, ion beam etching, cleaning, and plating. And it is novel, low-cost and easy to implement, especially replaces traditional reaction ion etching with photoresist thermal melting, largely reducing cost, and shortening making cycle, and it can reduce parts of system and eliminate astigmatism and coma of optical system.

The invention discloses a cylindrical lens based Wadsworth grating imaging spectrometer, belongs to the spectrum technology field, and aims to solve the problems that wavelength astigmatism in a working waveband of a conventional Wadsworth spectrometer system increases along with expansion of the working waveband, spectrum curving is caused, flat image fields are not easy to realize, and the Wadsworth spectrometer system is difficult to apply to imaging spectrometers. The grating imaging spectrometer comprises a slit, a collimating lens, a concave grating and a cylindrical lens. The collimating lens is an off-axis parabolic lens, and the slit is positioned at the focal position of the collimating lens. Divergent light emitted from the slit becomes a parallel beam after passing through the collimating lens, the parallel beam enters the concave grating, and the central wavelength of an outgoing beam subjected to chromatic dispersion by the concave grating is located on the normal of the concave grating. The outgoing chromatic dispersion beam is re-focused on an image surface after passing through the cylindrical lens. The placement position and the inclination angle of the cylindrical lens between the concave grating and the image surface, and the wedge angle of the cylindrical lens need to meet some conditions.

A corrector (1) for the axial and off-axial beam path of a particle-optical system, comprises a first (10) and a second (20) correction piece, which are disposed one behind the other in the beam path (2) on an optical axis (3). Each correction piece (10, 20) comprises four successive multipole elements (11, 12, 13, 14; 24, 23, 22, 21) disposed symmetrically with respect to a center plane (5) and with the following fields: wherein the first (11; 24) and the fourth (14; 21) multipole elements of the multipole elements (11, 12, 13, 14; 24, 23, 22, 21) are used to generate quadrupole fields (11′, 14′; 24′, 21′) and the second (12; 23) and third (13; 22) are used to generate octupole fields (12′″, 13′″; 23′″,22′″) and quadrupole fields (12′, 13′; 23′,22′), wherein the latter are superposed magnetic (12′, 13′; 23′, 22′) and electric fields (12″, 13″; 23″, 22″), wherein the quadrupole fields (11′, 12′, 13′, 14′; 24′, 23′, 22′, 21′) of all four multipole elements (11, 12, 13, 14; 24, 23, 22,21) are rotated from one to the next through 90°. An astigmatism of third order is corrected by a central multipole element disposed in the center plane and generating an octupole field.

The invention provides a method for visually testing the resolution of each imaging area of a digital camera, which comprises the following steps of: converting a photo into a gray level image; calculating the diameter of the image of the photo; performing vignetting glossiness loss correction; performing binaryzation on the image; marking a plurality of pixel blocks as foreground pixel blocks; removing the foreground pixel blocks from the corners of the photo or the foreground pixel blocks with small areas; by taking the centre of the image of the photo as the centre of a circle, establishing a plurality of concentric circles to divide the image of the photo into a plurality of circular areas and representing image divergence degrees in each circular area by using rectangular images; and according to neighboring relations of the circular areas, sequentially splicing all the obtained rectangular images into a test result graph. The method not only can determine a clear and available area of the photo shot by a set of shooting equipment, but also can compare the resolution of the fully-shot photo with that of middle screenshots of different ratios to find a shooting method through which maximum resolution can be realized, thereby ensuring that the definition in copying can be maximal or the number of the shot photos is the smallest on the premise of ensuring the definition.

Arrangements for the point-to-point imaging of a broad spectrum of electromagnetic radiation and ultrasound at large angles of incidence employ matched pairs of spherically bent reflectors to eliminate astigmatic imaging errors. Matched pairs of spherically bent crystals or spherically bent multi-layers are used for X-rays and EUV radiation; and matched pairs of spherically bent mirrors that are appropriate for the type of radiation are used with microwaves, infrared and visible light, or ultrasound. The arrangements encompass the two cases, where the Bragg angle—the complement to the angle of incidence in optics—is between 45° and 90° on both crystals / mirrors or between 0° and 45° on the first crystal / mirror and between 45° and 90° on the second crystal / mirror, where the angles of convergence and divergence are equal. For x-rays and EUV radiation, also the Bragg condition is satisfied on both spherically bent crystals / multi-layers.

The present invention provides a microscope objective lens. The microscope objective lens comprises 14 sheets of spherical lenses which are arranged in a coaxial mode. The 14 sheets of spherical lenses comprise in order from an object side to an image side: a first lens (L1), a second lens (L2), a third lens (L3), a fourth lens (L4), a fifth lens (L5), a sixth lens (L6), a seventh lens (L7), an eighth lens (L8), a ninth lens (L9), a tenth lens (L10),an eleventh lens (L11), a twelfth lens (L12), a thirteenth lens (L13) and a fourteen lens (L14). The microscope objective lens obviously increasesthe view field of the object side while ensuring the high numerical aperture and the high resolution to achieve apochromatism from 500nm to 800nm, greatly eliminates spherical aberration, coma, astigmatism, field curvature, distortion, chromatic difference of magnification and axial chromatic aberration, meets the flat field apochromatism objective lens demand and achieves the technical demand ofa wide field of view (namely a large visual field number and a low range) and a high numerical aperture.

The aperture real image transfer unit for the transmission in the high power laser system is composed of the circular aperture diaphragm, the spatial filter and the diaphragm with zigzag type soft edge. The spatial filter consists of the input lens, the filtering pinhole and the output lens. The filtering pinhole is positionted in the confocal point of the input lens and the output lens. The position relations of the said composed components satisfy the following expression: d2=dM-d1m2. The invention can eliminate astigmatism caused by virtual image transmission and restrain the diffraction modulation and the components of high frequency spectrum caused by the linear and nonlinear effects. The physical results are as following: laser beam near field fill factor is raised from 20-30% to 50%, the terminal is raised from 20-30 % to 50%, the quality of focal spot is 5 time better than the diffraction limit and the output energy is raised one time.

A holographic laser scanning system for producing a highly defined 3-D scanning volume for omni-directional laser scanning of bar code symbols therein having a minimum element width on the order of about 0.017 inches or less. The holographic laser scanning system comprise a housing, a plurality of laser sources, a holographic scanning disc and a plurality of photodetectors. The plurality of lasr sources are disposed within the housing, for producing a plurality of laser beams. The holographic scanning disc is disposed within the housing, and has a plurality of holographic optical elements for scanning the laser beams and producing a plurality of laser scanning planes for scanning a code symbol. Each laser scanning plane has predefined beam characteristics and is spatially confined within a highly-defined 3-D scanning volume having at least three focal zones, a depth of field of at least 10 inches, and a scanning volume of at least 1,440 cubic inches. The plurality of laser scanning planes intersect within the highly defined 3-D scanning volume and the predefined beam characteristics of the laser scanning planes cooperate within the highly defined 3-D scanning volume so as to produce an omnidirectional laser scanning pattern for omnidirectional scanning therewithin, code symbols having a minimum element width on the order of about 0.017 inches or less.

The invention relates to bar code identifying and reading equipment. The camera comprises a shell, and a camera unit and a circuit board which are arranged in the shell, The device further comprises agroove-shaped view-finding window. A hole is formed in the front face of the shell. The groove type view finding window is sleeved in the hole; the depth value D1 of the groove type view finding window is greater than or equal to 10 mm; the camera shooting unit comprises at least two camera shooting modules; each camera module comprises a lens and an image sensor; wherein each lens is fixed at the bottom of the framing window, each lens collects a bar code image through a window of the groove-shaped framing window, and each image sensor receives an optical signal incident from the lens, converts the optical signal into an electric signal and sends the electric signal to a processor on the circuit board for decoding to obtain bar code information. The bar code reading device can be provided with a plurality of camera modules, code scanning requirements of multiple modes in different brightness environments can be met at the same time, and meanwhile, the view finding window is arrangedto limit incident angles of stray light and improve definition of bar code images.

A holographic laser scanning system comprising a support disc rotatable about an axis of rotation, and having an inner perimeter, an outer perimeter, and an available light collecting region defined between the inner perimeter and the outer perimeter. A laser light source produce a laser beam having first and second components characterized by first and second polarization states, respectively. A plurality of holographic optical elements are supported on the support disc between the inner and outer perimeters, for scanning the laser beam and producing a laser scanning pattern for scanning a code symbol. Each holographic optical element has a beam steering portion disposed adjacent the outer perimeter for scanning the laser beam, and a light collecting portion disposed between the inner and outer perimeters for collecting laser light reflected off a code symbol scanned by the laser beam. The beam steering portion of each holographic optical element has a light diffraction efficiency that is optimized for the first polarization state of the laser beam incident thereon, and the light collecting portion of each holographic optical element has a light diffraction efficiency optimized for the second polarization state of laser light reflected off the scanned code symbol. A photodetector is provided for detecting laser light reflected off the scanned code symbol. A polarization-selective filter is disposed before photodetector for transmitting collected laser light having second polarization state and blocking collected laser light having the first polarization state, thereby reducing the effects of glare produced when the laser beam scans bar code symbols on glossy substrates.

The invention relates to the technical field of optical imaging devices, and particularly discloses a camera lens, a camera module, electronic equipment and an automobile. The camera lens comprises afirst lens, a second lens, a third lens, a fourth lens, a fifth lens and a sixth lens which are sequentially arranged from an object side to an image side, wherein the first lens element has negativerefractive power, the second lens element has negative refractive power, the third lens element has positive refractive power. the fourth lens element has positive refractive power, the fifth lens element has negative refractive power, The sixth lens element has positive refractive power. The camera lens can directly keep small size and light weight without increasing the number of lens pieces, can keep good optical performance, and can well capture details of a shot object.

The bar code reading device comprises a shell, a groove-shaped view finding window with openings in the two ends, a camera module and a circuit board, the camera module and the circuit board are arranged in the shell, a hole is formed in the front face of the shell, and the groove-shaped view finding window is arranged in the hole in a sleeved mode; wherein the depth value D1 of the groove-shapedview finding window is greater than or equal to 10 mm, and the lens of the camera module collects a bar code image through the groove-shaped view finding window and then transmits the bar code image to a processor on the circuit board for decoding to obtain bar code information. According to the bar code identifying and reading device, through the deep groove-shaped view finding window and the fluctuation arranged on the side wall of the groove-shaped view finding window, stray light is effectively prevented from entering the lens, and therefore a clear bar code image is captured in a long distance.

The invention belongs to the medical appliance technical field and relates to a corneal cross-linking instrument. The corneal cross-linking instrument comprises a light source; the light source is installed at the upper part of a light source base; the middle of the light source base is provided with a light adjustment disk and a lens group; the lower part of the light source base is connected with a lens mounting seat; and the lower part of the lens mounting seat is provided with a lens. With the corneal cross-linking instrument of the invention adopted, stray light of a light beam can be eliminated, so that a light spot formed by a light beam emitted by the light source can be uniform, and the edge of the light spot is neat, and the size of the light spot is adjustable.

The invention provides a laser radar detection device. The device comprises a curved surface cover body, a laser, a first lens, a detector and a second lens. An emergent light beam of the laser is emitted to a measured object after passing through the first lens and the curved surface cover body in sequence to form a transmitting light path; the normal direction of the intersection point of the first optical axis of the first lens and the curved surface cover body coincides with the first optical axis; a reflected light beam reflected by the measured object sequentially passes through the cover body and the second lens and enters the detector to form a receiving optical path; and the normal direction of the intersection point of the second optical axis of the second lens and the curved surface cover body coincides with the second optical axis. According to the laser radar detection device provided by the invention, the first optical axis and the second optical axis are set to coincidewith the normal direction of the intersection point of each optical axis and the curved surface; the transmitting light path and the receiving light path are not influenced by the shape of the curvedsurface cover body, astigmatism of the transmitting light path and the receiving light path can be eliminated, the quality and the energy of light spots irradiated to a measured object by outgoing light beams are improved, and therefore, the light energy received by the detector and the detection performance of the laser radar are improved.

The invention relates to a probe type fluorescent confocal endoscope coupling objective lens optical system. The probe type fluorescent confocal endoscope coupling objective lens optical system comprises a diaphragm, a first lens, a second lens, a first lens group, a second lens group and a seventh lens which are sequentially arranged from an object plane to an image plane along an optical axis, wherein each of the first lens group and the first lens group is a double-gluing lens; the first lens group comprises a third lens and a fourth lens which are sequentially arranged from the object plane to the image plane along the optical axis; and the second lens group comprises a fifth lens and a sixth lens which are sequentially arranged from the object plane to the image plane along the optical axis. The coupling objective lens optical system provided by the invention basically eliminates spherical aberration, coma, astigmatism, field curvature, distortion and axial chromatic aberration, and meets the requirements of a flat-field apochromatic objective lens; and the axial difference between the optimal focus point of the edge view field and the optimal focus point of the center view field is smaller than 2 lambda / NA2, the achromatic aberration of 515 nm light and 550 nm light is eliminated, and the axial chromatic aberration of 488 nm light and 515 nm light is smaller than 2 lambda / NA2, wherein lambda is the central wavelength, and NA is the numerical aperture of the coupling objective optical system.

The invention relates to a preparation method of a double-sided composite thinned and zooming myopic lens, and belongs to the technical field of optical lens design. According to the invention, the method comprises the following steps: S1, establishing a front surface mathematical model and a rear surface mathematical model in optical software; S2, establishing an evaluation function including theastigmatism optimization value and the lens edge thickness; and S3, inputting structural parameters of the lens blank, and successively optimizing by applying a least square method to obtain data ofthe front surface and the rear surface of the lens. The edge thickness of the lens prepared by the preparation method of the double-sided composite thinned and zooming myopic lens is reduced by 20%-30% compared with that of a spherical surface; the zoom range from the optical center to the edge degree not only reaches + / -4.00 D, but zooming can be performed according to an optometry prescription when the diameter of the lens is 10-40mm, and astigmatism is basically eliminated when the diameter of the lens is 50mm.

The invention provides an environment-friendly body building rotary massager capable of promoting motion of skin, accelerating blood circulation, eliminating fatigue of optic and cranial nerves, delaying senility and strengthening the body, which consists of a body building object (1), magnetism (2), rotary massage balls (3), a seat shell (4), a micro motor (5), a bearing (6), a driving wheel (7), a hood (8), a microcomputer (9), a driven wheel (10), a mask (11), massage balls (12), a handle (13), movable plates (14) and a belt (15). The rotary and retractable rotary massage balls have massage, extruding massage, rolling massage and rotary massage functions and an eyesight improving, cosmetic and magnetic, powder, cream, liquid, gas brain-strengthening objects and the like act on channels and collaterals of the skin in three aspects, so that the environment-friendly body building rotary massager achieves the effects of preventing, relieving and eliminating various diseases such as myopia, hyperopia, astigmatism, presbyopia, dark pouches, pouches, wrinkles, color spots, rhinitis, toothache, tinnitus, liposotrichia, dizzy of the head and dim of sight, forgettery, insomnia, migraine, neurasthenia, hypertension, lumbocrural pain, tumours and the like, improves the work efficiency, makes people keep young, and is particularly suitable for curved surfaces, rugged faces, brains and the whole body. The environment-friendly body building rotary massager has the advantages of simple structure, convenience and practicability, and is popular.

The invention provides an electrically pumped random laser device based on a dual SiO2-ZnO structure and a preparation method and application thereof. The electrically pumped random laser device comprises a first ZnO thin film, a first SiO2 thin film, a second ZnO thin film, a second SiO2 thin film and a semi-transparent electrode which are sequentially deposited on the front face of a silicon substrate from bottom to top, wherein an ohmic contact electrode is deposited on the back face of the silicon substrate. The invention also provides a preparation method of the laser device. The preparation method comprises the following steps of: 1) depositing the first ZnO thin film on the front face of the silicon substrate; 2) depositing the first SiO2 thin film on the first ZnO thin film; 3) depositing the second ZnO thin film on the first SiO2 thin film; 4) depositing the second SiO2 thin film on the second ZnO thin film; 5) sputtering the semi-transparent electrode on the second SiO2 thin film, and sputtering the ohmic contact electrode on the back face of the silicon substrate, thus obtaining the electrically pumped random laser device based on the dual SiO2-ZnO structure. According to the electrically pumped random laser device based on the dual SiO2-ZnO structure, the threshold current of is obviously reduced and the light output power is obviously improved. Moreover, the preparation method is simple, can be compatible with the conventional complementary metal oxide semiconductor (CMOS) process and is favorable for large-scale production and application of devices.

The invention discloses a varifocal optical system. The system sequentially comprises a first fixed lens group with positive focal power, a main zoom lens group with negative focal power, a diaphragm,a second fixed lens group with positive focal power, a focusing lens group with negative focal power, an auxiliary zoom lens group with positive focal power and an imaging surface from an object plane side to an image plane side; the auxiliary zoom lens groups are in one-to-one correspondence with the main zoom lens groups in position and move from the object side to the image plane side along the optical axis. The focusing lens group moves correspondingly to the position, the imaging wavelength, the temperature and the imaging object distance of the main zoom lens group along the optical axis, and the zoom is corrected and focused, so that stable imaging can be realized on an imaging surface in a focal length changing process. While 4K resolution, large aperture and infrared confocal performance are realized, the total length of the optical system is greatly shortened, the structure is more compact, and the popularization of 4K camera shooting is facilitated.

The invention relates to a barcode reading device, comprising a housing, a slot-shaped viewing window with openings at both ends, a camera module and a circuit board arranged in the housing, a hole is arranged on the front of the housing, and the slot-shaped viewing window Set in the hole; the depth value D of the slot-shaped viewfinder window 1 ≥10mm, the lens of the camera module captures the barcode image through the slot-shaped viewfinder, and then transmits it to the processor on the circuit board for decoding to obtain the barcode information. The barcode reading device of the present invention effectively blocks stray light from entering the lens through a deep slot-shaped viewing window and undulations on the side wall of the slot-shaped viewing window, thereby realizing long-distance capture of clear barcode images.