53results about How to "Eliminate astigmatism" patented technology

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.

A laser scanner of ultra-compact and modular design capable of reading bar and other types of graphical indicia, and also a method of designing and operating the same for use in diverse applications.

A holographic laser scanning system employing laser beam production module with optical components geometrically constrained so as to be capable of producing a laser scanning beam having a controlled beam aspect-ratio substantially reduced astigmatism and minimal dispersion during laser beam scanning operations.

The first scanner generates an omnidirectional laser scanning pattern within a large 3-D scanning volume in order to detect the location of a code symbol therewithin and produce data indicative of its location therewithin. Using this location data, the second scanner produces a high density scanning pattern to aggressively scan the region in which the code symbol has been detected, and collect scan data for decode processing. In the illustrative embodiment, the first scanner is realized as a multiple-focal plane holographic scanner, whereas the second scanner is realized as a high-speed 2-D scanner. By virtue of the system and method of the present invention, it is now possible to read bar code symbols located anywhere within very large volume of space, with a high degree of accuracy hitherto impossible using prior art techniques.

An observation apparatus is provided. An apex angle of a contact prism is inputted by operating an apex angle setting knob of a control panel. A fining angle of the contact prism is inputted by operating a fitting angle setting knob. A control unit determines the amount of correction for astigmatism of a left observation optical system and the amount of correction for astigmatism of a right observation optical system based on a recognized observation magnification and the inputted apex angle. An axial angle for the astigmatism of the left observation optical system and an axial angle for the astigmatism of the right observation optical system are determined based on the inputted fitting angle. Variable cross cylinder lens rotating drive units are controlled to rotate cylinder lenses of each of the right and left observation optical systems, thereby obtaining the determined axial angle and the determined amount of correction.

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 relates to a reflection-type confocal scanning retina imaging system based on adaptive optics, which can accurately obtain the high-resolution images of vital human eye retinae in real time and comprises a light source, a reflection-type beam shrinking and expanding system, a two-dimension scanning galvanometer, a Hartmann sensor, a deformable mirror, a photoelectric detection system, a data acquisition and processing system and a contraocular sighting target system. Lasers emitted from the light source are hit into human eye ground; light reflected from the eye ground returns along the original path, enters the photoelectric detection system and passes through the data acquisition and processing system to obtain the real-time images of the human eye ground. Simultaneously, an adaptive optics system comprising the Hartmann sensor and the deformable mirror can synchronously detect and correct human eye aberration, and thereby, the high resolution of the images is ensured.

The invention discloses a laser beam astigmatism compensation method and a laser processing system. By adding an astigmatism compensation device in the external optical path of the laser processing system, the astigmatism is generated after the laser beam passes through the astigmatism compensation device; the astigmatism compensation device is adjusted The rotation angle of the optical components in the astigmatism compensation device changes the size and direction of the astigmatism, so that the astigmatism generated by the astigmatism compensation device is equal to the astigmatism of the original laser processing system, and the direction is opposite. Astigmatism is reverse compensated. The present invention can reduce the astigmatism of the laser beam that finally reaches the processing table, so that both the focused and defocused spots are a circular spot, and the consistency of the width and depth of the scribe line in any direction is improved when laser processing is performed in the defocused state. Eliminating the astigmatism problem of the laser beam can significantly improve the quality of laser processing, improve the processing effect, improve the yield rate, and reduce the processing cost.

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.