107results about How to "Increase focal length" patented technology

A vehicle vision system includes a vehicle having first and second spatially separated image capture sensors. The first image capture device has a first field of view having a first field of view portion at least partially overlapping a field of view portion of a second field of view of the second image capture device. A control receives a first image input from the first image capture sensor and a second image input from the second image capture sensor and generates a composite image synthesized from the first image input and the second image input. A display system displays the composite image.

Ultrashort pulse laser processing bores, welds or cuts objects (work pieces) by converging ultrashort laser pulses by a lens on the objects (work pieces) positioned at the focus and heating small spots or narrow lines on the objects (work pieces). Shortage of a focal depth of the lens prevents the ultrashort pulse laser processing from positioning the object (a work piece) and forming a deep, constant-diameter cylindrical hole. Z-parameter is defined to be Z=2fcΔt/Δi², where Δt is a FWHM pulse width of the ultrashort pulse laser, Δi is a FWHM beam diameter of the ultrashort pulse, f is a focal length of the lens and c is the light velocity in vacuum. Selection of an optical system including a diffraction-type lens which gives the Z-parameter less than 1 (Z<1) prolongs the focal depth. Expansion of the focal depth facilitates the positioning of objects (work pieces) and enables the ultrashort pulse laser apparatus to bore a deep, constant-diameter cylindrical hole.

An iris recognition lens system including a first lens and a second lens disposed on an optical axis and sequentially from an object to take an image of an iris and a pupil. A front part of the first lens includes a reflecting area in a central portion and a transmitting area in a circumferential portion. A rear part of the first lens includes a concave transmitting area in a central portion and a reflecting area in a circumferential portion. The second lens is disposed at a rear of the transmitting area in the central portion of the rear part of the first lens. A plurality of reflecting areas and a plurality of transmitting areas are provided in a single lens in order to reduce the length of the lens and increase a focal length, thereby reducing the length of the entire iris recognition lens system.

A numerical aperture (NA) controlling unit and a variable optical probe including the same are provided. The NA controlling unit includes: an aperture adjustment unit which controls an aperture through which light is transmitted; and a focus control unit that is disposed in a predetermined position with respect to the aperture adjustment unit, that focuses light transmitted through the aperture, and that has an adjustable focal length. The variable optical probe includes: a light transmission unit; a collimator that collimates light transmitted through the light transmission unit into parallel light; an NA controlling unit that focuses light on a sample to be inspected; and a scanner that varies a path of light transmitted through the light transmission unit such that a predetermined region of the sample is scanned by light that passes through the NA controlling unit.

The invention belongs to the technical field of optical imaging and detecting and relates to a bilateral dislocation differential confocal element parameter measuring method. The method includes the steps that dislocation differential subtracting processing is conducted on the two sides of a confocal axial characteristic data set measured by the starting points and the ending points of all various size parameters including the curvature radius, the lens thickness, the refractive rate, the focal distance and the interval, and therefore the positioning precision of the starting points and the ending points of the size parameters is improved, and the measuring precision of optical elements of the curvature radius, the lens thickness, the refractive rate, the focal distance, the interval and the like is improved. According to the bilateral dislocation differential confocal element parameter measuring method, due to the fact that two sections of data, close to the position of the full width at half maximum and very sensitive to axial displacement, of a confocal characteristic curve are used for conducting the dislocation differential subtracting processing, the position, calculated by the data sections, of the extreme point of the confocal characteristic curve is more sensitive and more accurate than the position, calculated through an existing confocal characteristic curve top fitting method, of the extreme point of the confocal characteristic curve, according to the result of the bilateral dislocation differential confocal element parameter measuring method, under the condition that the confocal element parameter system structure is not changed, the axial focusing capability, the signal-to-noise ratio and the like of the system can be obviously improved.

A variable magnification optical system consists of a negative first lens group, a stop that is fixed relative to an image plane during magnification change, and a positive second lens group, which are in this order from an object side. A distance between the first lens group and the second lens group in an optical axis direction becomes shorter when magnification is changed from a wide-angle end to a telephoto end. The first lens group consists of a positive lens having a convex object-side surface and two negative lenses, in this order from the object side. The variable magnification optical system satisfies the following formula (1) about Abbe number νd1 of the positive lens in the first lens group for d-line:

25.5<νd1<50  (1).

An ultrasonic imaging apparatus and method combines dynamically focused reception and coded transmission/reception technologies by inexpensive circuitry. A receive aperture is divided into smaller apertures. Correspondingly, a receive beam former is divided into receive sub-beam formers 36a to 36n by which a phase alignment and summing process is performed. Thereafter, coded signals are compressed in decoders 37a to 37n in a time axis direction. Output signals from the decoders are once again subjected to a phase alignment and summing process in a second beam former.

An optical system is provided for use in a vehicle head-up display including a display panel for displaying drive information image, a backlight unit for irradiating light toward the display panel and an optical system for adjusting the size and focal distance of the drive information image projected from the display panel toward a windshield of a motor vehicle. The optical system includes a pre-lens reflection mirror array for reflecting the drive information image projected from the display panel to travel along a first roundabout path, a lens array for adjusting the size and focal distance of the drive information image reflected by the pre-lens reflection mirror array, and a post-lens reflection mirror array for reflecting the drive information image coming from the display panel toward the windshield to travel along a second roundabout path.

An image forming optical system comprising, in order from the object side: a first lens group G1 that is fixed during zooming and includes a reflecting optical element for bending an optical path; a second lens group G2 having a negative refracting power and movable during zooming; a third lens group G3 having a positive refracting power; a fourth lens group G4 having a positive refracting power; and a rearmost lens group GR, wherein during zooming from the wide angle end to the telephoto end, the third lens group G3 moves on the optical axis toward the object side, characterized in that the rearmost lens group GR satisfies the following condition:

0.95<βRw<2.5  (1-1).

A lens for image pickup is provided in which various aberrations are corrected satisfactorily, the optical length is at maximum approximately 6 mm, and moreover a sufficient back focus is secured. This lens for image pickup comprises a first lens, an aperture diaphragm, and a second lens, positioned in this order from the object side toward the image side. The first lens is a resin lens with a meniscus shape, with the convex surface facing the object side, and having positive refractive power. The second lens is a resin lens with a meniscus shape, with the convex surface facing the image side, and having positive refractive power.

The invention discloses a shortwave infrared telescope lens which is formed by the configuration of a first lens group with positive focal power, a second lens group with negative focal power and a third lens group with positive focal power from an object side orderly. The second lens group is formed by single lens elements. In the time of focusing, the second lens group moves along an optical axis, and the first lens group and the third lens group are fixed relative to an imaging surface. The invention provides the shortwave infrared telescope lens with a small size, light weight, large diameter, high resolution, excellent imaging performance and an inner focusing mode.

A bi-directional fiber optic transceiver includes a laser diode, a photodiode, first and second lenses, all of which share a common linear optical axis, and a housing. The first lens may have transmission increasing film thereon. The second lens may have a reflection increasing film thereon. An optical splitter may be between the first and second lenses. The first and/or second lenses may be spherical, hemispherical or aspheric. The transceiver size is reduced so that a circuit board can accommodate more components or be smaller in size. Utilizing hemispherical lenses can greatly increase the coupling ratio of the optical links between the photodiode, fiber and laser diode. Utilizing aspheric lenses with high coupling can serve high power output requirements. Use of spherical lenses (which extend the focal length) with aspheric lenses enables LD TO assemblies in individual housings to serve in various products.