88results about How to "High contrast image" patented technology

PCT No. PCT/US95/02155 Sec. 371 Date Dec. 22, 1997 Sec. 102(e) Date Dec. 22, 1997 PCT Filed Feb. 21, 1995 PCT Pub. No. WO95/22804 PCT Pub. Date Aug. 24, 1995A method and ultra-compact system has been developed for illuminating and detecting the surface topography of an object such as the finger (4) of an individual. The system (8) is capable of producing high-contrast images which can be electronically transmitted in real-time, or stored using electronic or photographic recording devices. Light traveling within a light transmitting substrate (2) is redirected by a slanted-fringed light diffractive grating preferably embodied within a volume hologram (3). The volume hologram (3), either of the reflection or transmission type, is attached to the light transmitting substrate (2). and functions to diffract light striking thereupon and illuminate an object having topographical surface structure. After being spatially and intensity modulated in accordance with topographical details of the illuminated object, the insulated light passes back through the light transmitting substrate (2) and the volume hologram (3), onto an image detection array. for subsequent analysis. Each of the disclosed embodiments has a compact geometry suitable for use in diverse object identification applications.

A portable, lightweight digital imaging device uses a slit scanning arrangement to obtain an image of the eye, in particular the retina. In at least one embodiment, a digital retinal imaging device includes an illumination source operable to produce a source beam, wherein the source beam defines an illumination pathway, a scanning mechanism operable to cause a scanning motion of the illumination pathway in one dimension with respect to a target, an optical element situated within the illumination pathway, the optical element operable to focus the illumination pathway into an illumination slit at a plane conjugate to the target, wherein the illumination slit is slit shaped, a first two dimensional detector array operable to detect illumination returning from the target and acquire one or more data sets from the detected illumination, wherein the returning illumination defines a detection pathway, and a shaping mechanism positioned within the illumination pathway, wherein the shaping mechanism shapes the source beam into at least one arc at a plane conjugate to the pupil. In at least one exemplary embodiment, the digital retinal imaging device is operable to minimize at least one aberration from the optical element or an unwanted reflection from the target or a reflection from a device.

This invention provides an infrared illuminator and camera system for imaging of auto vehicle license plates. The system works in ambient light conditions, ranging from bright sunlight, to dim light, to dark, to zero ambient light. It yields high-contrast imaging of the letters and numbers on retro-reflective license plates. The images of the license letter and number combinations can be read manually by a remote operator. They can be converted to text format with optical character recognition computer hardware and software. The text data can then be compared to data files listing license numbers to provide further data about the owner of a licensed vehicle. A decision can be made quickly about whether to allow a vehicle to proceed through a gate, or whether to take other action. The system uses a mono camera that is enhanced for infrared sensitivity and combined with a high power infrared illuminator to maximize range at night, and with shutter speeds set up to capture clear license plate pictures even with fast moving vehicles and even with their headlights on and interfering with human observation of the license plates. Optical filtering to pass infrared in the range of the illuminator and to reduce light outside this range, combines with a lens set up, to avoid vertical smear and sensor overload caused by headlights at night and by highlight reflected glare from the sun in daytime.

An method and device suitable for navigation on a wide variety of surfaces is introduced. Specular reflection is used to determine relative motion over typical surfaces. A specific application is a computer mouse.

A hand held industrial identification symbol reader projects diffuse illumination onto a region of interest to produce high contrast images of symbols. The diffuse illumination is particularly well suited for producing images of symbols that are marked directly on objects. The diffuse illumination is created through the use of an optically translucent diffuser having a generally tapered shape that distributes diffuse illumination throughout the field of view of the reader. The diffuse illumination can be supplemented with dark field illumination using selectively actuated illumination sources.

A portable, lightweight digital imaging device uses a slit scanning arrangement to obtain an image of the eye, in particular the retina. The scanning arrangement reduces the amount of target area illuminated at a time, thereby reducing the amount of unwanted light scatter and providing a higher contrast image. A detection arrangement receives the light remitted from the retinal plane and produces an image. The device is operable under battery power and ambient light conditions, such as outdoor or room lighting. The device is noncontact and does not require that the pupil of the eye be dilated with drops. The device can be used by personnel who do not have specialized training in the eye, such as emergency personnel, pediatricians, general practitioners, or volunteer or otherwise unskilled screening personnel. Images can be viewed in the device or transmitted to a remote location. The device can also be used to provide images of the anterior segment of the eye, or other small structures. Visible wavelength light is not required to produce images of most important structures in the retina, thereby increasing the comfort and safety of the device. Flexible and moderate cost confocal and fluorescent imaging, multiply scattered light images, and image sharpening are further functionalities possible with the device.

A method for single photon counting transmission computed tomography (CT) is described. The method is based on an apparatus consisting of a radiation source and detectors on an opposite side of the subject from the source. The radiation source is for example an X-ray tube. The detectors are independently connected to parallel, fast, low-noise processing electronics capable of recording and counting individual X-ray photons at very high rate. In one embodiment of the invention, said detector is made of a scintillator coupled to a photodetector. The photodetector can be an avalanche photodiode (APD). The method comprises the steps of: directing the low energy radiation source toward the subject; detecting the radiation transmitted through the subject towards the detectors and recording the position and energy of each individual X-ray photon; rotating the radiation source and detectors around the subject; recording data for each position of the radiation source and detectors around the subject to form projections; and creating a CT image from the recorded projection data. The proposed method allows enhancing CT image contrast and reducing radiation dose to the patient by counting individual X-ray photons.

A method for inspecting the packaging of a packaged product is presented wherein the packaged product includes a tray and a film enwrapping a product carried on the tray forming a packaging. The method includes providing a tray and providing a packaging film material which contains an additive for producing a high contrasting image under non-visible light when compared to the tray. The additive does not affect the spectral properties of the packaging film material in visible light. The tray and transparent film are illuminated with a non-visible light. The contrasting image of the tray and transparent film is viewed for determining the presence and configuration of the packaging. The configuration of the packaging is analyzed based upon a predetermined expected packaging profile and it is determined if the packaging is substantially similar to the predetermined expected packaging profile constituting an acceptable packaging.

A novel transparent film is disclosed. Re (λ) and Rth (λ) of the film defined by the following formulae (I) and (II) satisfy the following formulae (III) and (IV):

Re (λ)=(nx−ny)×d,  (I)

Rth (λ)={(nx+ny)/2−nz}×d,  (II)

0≦|Re(630)|≦50,  (III)

Rth (400)×Rth (700)≦0, and 0<|Rth (700)−Rth (400)|≦150,  (IV)

wherein Re (λ) means an in-plane retardation value at a wavelength λ nm (unit: nm); Rth (λ) means a thickness-direction retardation value at a wavelength λ nm (unit: nm); nx means a refractive index in the in-plane slow-axis direction; ny means a refractive index in the in-plane fast-axis direction; nz means a refractive index in the film thickness direction; and d means a thickness of the film.

A partially coherent light beam from a light source is split between a probe light beam toward an observation object and a reference light beam toward a fixed reflective surface. The frequency of the probe light beam is shifted by optical-modulation means. The probe light beam whose frequency has been shifted is swept in a direction of an optical axis and in a direction orthogonal thereto to scan the object two-dimensionally. Reflected light beam from the object is combined with the reference light beam to generate interference light. A detector receives a time-based interference signal from the interference light obtained from the movement of the probe light beam in the direction of the optical axis and the sweeping in the direction orthogonal to the optical axis to derive therefrom reflection intensity data of the object. In such a configuration, the mechanically moving portion is disposed in the probe optical path. Therefore, changes in the interference characteristics of the light that accompany the mechanical scanning are less likely to occur and optical adjustments are also made easy.

A projection display system is disclosed including a laser light source, projection lens or mirror, and screen. This invention enables a decorative screen which hides a display and matches near-by furniture. This invention also discloses a tiny cost-effective laser light source for projection displays.

An organic electroluminescent device, comprises a plurality of pixels each including a light-emitting element, and a drive device adjusting a light-emission period of the light-emitting element included in each of the pixels in accordance with a luminance ratio of an image to be displayed.

A highly corrected relay system for medical endoscopes or the like is provided. The system includes a plurality of bonded lenses that are selected to provide color correction from the blue region of the spectrum through to the near infrared region of the spectrum. The system allows co-located visible and near infrared images to be resolved on a single detector.

A light-emitting element includes a cathode, an anode, a red-light-emitting layer that is disposed between the cathode and the anode and emits red light, a blue-light-emitting layer that is disposed between the red-light-emitting layer and the cathode and emits blue light, a green-light-emitting layer that is disposed between the blue-light-emitting layer and the cathode and emits green light, and an intermediate layer that is disposed between and in contact with the red-light-emitting layer and the blue-light-emitting layer and functions so as to control the transfer of positive holes and electrons between the red-light-emitting layer and the blue-light-emitting layer, wherein the intermediate layer contains a first material and a second material different from the first material, the red-light-emitting layer contains a material of the same type as the first material, and each of the blue-light-emitting layer and the green-light-emitting layer contains a material of the same type as the second material.

It is desirable to achieve a co-incident investigative kV source for a therapeutic MV source—a so-called “beams-eye-view” source. It has been suggested that bremsstrahlung radiation from an electron window be employed; we propose a practical structure for achieving this which can switch easily between a therapeutic beam and a beam-eye-view diagnostic beam capable of offering good image resolution. Such a radiation source comprises an electron gun, a pair of targets locatable in the path of a beam produced by the electron gun, one target of the pair being of a material with a lower atomic number than the other, and an electron absorber insertable into and withdrawable from the path of the beam. In a preferred form, the electron gun is within a vacuum chamber, and the pair of targets are located at a boundary of the vacuum chamber. The lower atomic number target can be Nickel and the higher atomic number target Copper and/or Tungsten. The electron absorber can be Carbon, and can be located within the primary collimator, or within one of a plurality of primary collimators interchangeably locatable in the path of the beam. Such a radiation source can be included within a radiotherapy apparatus, to which the present invention further relates. A flat panel imaging device for this source can be optimised for low energy x-rays rather than high energy; Caesium Iodide-based panels are therefore suitable.

A novel liquid crystal display device is disclosed. The device comprises a first polarizing element and a second polarizing element which are disposed with their transmission axes perpendicular to each other, a liquid crystal layer disposed between the first and the second polarizing elements, and a first optically anisotropic layer disposed between the first or the second polarizing element and the liquid crystal layer, showing a positive in-plane retardation (Re) at λ1 and a negative Re at λ2, both of λ1 and λ2 (λ1≠λ2) are within a visible wavelength range, and its absolute value of a thickness-direction retardation at 550 nm, |Rth(550)|, is equal to or more than 50 nm.

A method of processing postal articles in an automatic address-reading system in which a multi-level gray scale image is formed of the surface of each article including address information, the multi-level gray scale image is transformed into a first binary image and the binary image is sent to an OCR unit for a first automatic evaluation of the address information, wherein a signature representative of a category of address information marks is extracted from the multi-level gray scale image and/or the binary image and/or the result of automatic data evaluation, the multi-level gray scale image is transformed again into a second binary image taking account of the category represented by the signature, and the second binary image is sent to an OCR unit in order to perform a second automatic evaluation.