Night vision

About: Night vision is a research topic. Over the lifetime, 6004 publications have been published within this topic receiving 67372 citations.

Asymmetric electrode incorporated 2D GeSe for self-biased and efficient photodetection.

Abstract: 2D layered germanium selenide (GeSe) with p-type conductivity is incorporated with asymmetric contact electrode of chromium/Gold (Cr/Au) and Palladium/Gold (Pd/Au) to design a self-biased, high speed and an efficient photodetector. The photoresponse under photovoltaic effect is investigated for the wavelengths of light (i.e. ~220, ~530 and ~850 nm). The device exhibited promising figures of merit required for efficient photodetection, specifically the Schottky barrier diode is highly sensitive to NIR light irradiation at zero voltage with good reproducibility, which is promising for the emergency application of fire detection and night vision. The high responsivity, detectivity, normalized photocurrent to dark current ratio (NPDR), noise equivalent power (NEP) and response time for illumination of light (~850 nm) are calculated to be 280 mA/W, 4.1 × 109 Jones, 3 × 107 W-1, 9.1 × 10-12 WHz-1/2 and 69 ms respectively. The obtained results suggested that p-GeSe is a novel candidate for SBD optoelectronics-based technologies.

Night vision reflex sight

Abstract: A passive night vision reflex sight with a wide F.O.V. and designed for attachment to a weapon, such as a rifle, is disclosed. The night vision reflex sight preferably is designed for use in combination with a night vision goggle; it can also be used as in daylight without such a goggle, however. When in place, it continues to allow the use of the daytime battle sight of the weapon. The night vision reflex sight comprises a sight for viewing an image of a scene along a line of sight, a photoreceptive sensor aligned with the line of sight and viewing the image, a battery powered red L.E.D., together with a reticle, a lens, and a filter for generating a pulsed or d.c. light and for directing it at the reflex sight, with the sight reflecting the pulsed or d.c. light into the photoreceptive sensor and superimposing it on the image. Preferably, the reticle is adjustable, the pulsed light is pulsed at a rate between about two to about twelve c.p.s. Preferably, the reflex sight is disposed within a housing baffled toward the front, and a demountable flared light shield having a flexible shutter is provided on the housing toward the rear. Preferably, the brightness of the pulsed light is adjustable.

Active night vision image intensity balancing system

Abstract: A vision system ( 10 ) for a vehicle ( 14 ) includes a light source ( 46 ) that generates an illumination beam ( 20 ). A receiver ( 62 ) generates a first image signal and a second image signal. The first image signal is generated in response to a reflected portion of the illumination beam ( 20 ). A controller is coupled to the light source ( 46 ) and the receiver ( 62 ). The controller generates an image in response to the first image signal and the second image signal.

Emerging Gene Therapies for Retinal Degenerations

Abstract: ### Introduction Our most cherished sense, vision, begins with the process of phototransduction, a process performed by the highly specialized photoreceptor cells of the retina: the rods and cones ([Rodieck, 1998][1]). Rod photoreceptor cells are needed for night vision, as they are able to respond

Vision screening for driver licensure

Abstract: Vision is the primary sensory input on which the driver depends. A decrease in visual skills with age could be an important causal or contributory factor in the driving difficulties experienced by the older driver. The crystalline lens within the eye shows functionally significant changes with age. It loses its elasticity, causing a decrease in the ability of the eye to accommodate or change focus. This loss begins around the age of 40, typically being compensated for with glasses or bifocals, and is complete by the age of 60 to 65. The lens yellows with age, contributing to changes in color vision, decreased light sensitivity, and decreased visual acuity. Glare susceptibility is increased. Cataracts, usually age related, should be removed and the optical power of the lens replaced by glasses, contact lenses, or implants. The pupil of the eye becomes smaller with age and loses its ability to dilate in dim light. Many disorders of the retina are associated with age. In the absence of disease, corrected visual acuity remains relatively constant from ages 20 to 50. After 50, corrected acuity begins to decrease, with a rapid decline after 60. The critical flicker frequency (CFF), the flicker rate beyond which flickering of light cannot be detected; dynamic visual acuity; and color discrimination show age-related declines. There is evidence of diminished cognitive capabilities, visual spatial judgment, and visually based motor responses with age. The purpose of this paper is to examine whether current vision standards and screening procedures for drivers are appropriate for identifying those with significant visual disabilities that are unsafe for driving. The following areas are covered: current state of the art in vision screening for driver licensure; relationship of vision and driving performance; bases for visual standards and screening procedures; vision screening implementation issues; merits of various aspects of vision screening; vision-screening policy decisions; recommended driver vision screening and standards; and research needs with regard to visual acuity and visual field tests.