Night vision

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

Driver behavior and performance using an infrared night vision enhancement system

Abstract: Nighttime driving is unsafe due in part to the poor visibility of low contrast objects. Night Vision Enhancement Systems (NVES) offer a potential solution to this problem. However, there are concerns regarding driver distraction, object recognition, behavior compensation and direct vision impairments that need to be addressed. Incorporating lessons learned from a preliminary NVES study, crash analyses, and prior NVES research, a field experiment was designed to evaluate NVES. The evaluation used a 2000 Cadillac DeVille with Night Vision. Younger and Older drivers drove the vehicle along a predefined route on both public and closed roads. Targets consisted of traffic cones and pedestrians. All cones were heated and painted either black or white. Pedestrians wore either white or black clothing and were either stationary or waving their arms. Drivers were asked to provide separate detection and recognition responses for objects detected with headlights or indirectly via NVES and report speed limits

Patient satisfaction following photorefractive keratectomy for myopia

Abstract: This study was conducted to evaluate the subjective response of patients who underwent photorefractive keratectomy (PRK) for myopia with the Summit Technology UV 200 LA excimer laser (Summit Technology, Inc., Waltham, Mass.) (3.5 to 5.0 mm diameter ablation zone) 36 months previously. One-hundred thirteen patients with preoperative myopia between -1.50 diopters (D) and -6.50 D with an ablation diameter of 3.5 mm to 5.0 mm answered a questionnaire at the 36-month examination. Sixty-two percent of patients had both eyes treated. Halo problems were experienced always by 34% of patients in the group, 26% sometimes, and 40% never. Permanent night vision problems were experienced by 40%; 30% reported them sometimes and 30% reported no problems at all. Sixty percent never needed to use glasses after treatment, 30% sometimes did, and 10% always wore glasses. Seventy percent of patients thought the results were very good; the remaining 30% experienced different degrees of halo and night vision problems.

Helicopter flights with night-vision goggles: Human factors aspects

Abstract: Night-vision goggles (NVGs) and, in particular, the advanced, helmet-mounted Aviators Night-Vision-Imaging System (ANVIS) allows helicopter pilots to perform low-level flight at night. It consists of light intensifier tubes which amplify low-intensity ambient illumination (star and moon light) and an optical system which together produce a bright image of the scene. However, these NVGs do not turn night into day, and, while they may often provide significant advantages over unaided night flight, they may also result in visual fatigue, high workload, and safety hazards. These problems reflect both system limitations and human-factors issues. A brief description of the technical characteristics of NVGs and of human night-vision capabilities is followed by a description and analysis of specific perceptual problems which occur with the use of NVGs in flight. Some of the issues addressed include: limitations imposed by a restricted field of view; problems related to binocular rivalry; the consequences of inappropriate focusing of the eye; the effects of ambient illumination levels and of various types of terrain on image quality; difficulties in distance and slope estimation; effects of dazzling; and visual fatigue and superimposed symbology. These issues are described and analyzed in terms of their possible consequences on helicopter pilot performance. The additional influence of individual differences among pilots is emphasized. Thermal imaging systems (forward looking infrared (FLIR)) are described briefly and compared to light intensifier systems (NVGs). Many of the phenomena which are described are not readily understood. More research is required to better understand the human-factors problems created by the use of NVGs and other night-vision aids, to enhance system design, and to improve training methods and simulation techniques.

Testing tool for determining the boresight retention of weapons brackets and night vision sights

Abstract: A testing tool that includes a light weight, highly accurate telescope and supplemental weights used to duplicate the weights of various night vision sights. The testing tool is mounted on a weapons adapter bracket for testing the accuracy of either or both the sight and the bracket. The supplemental weights include a main body block and auxiliary side weights in which the auxiliary side weights are bolted traversely through the main body block. The telescope is connected to one side of the main body block. The side of the main body block opposite the telescope is bottomed out on the bottom and beveled edges of a rectangular channel in a weapons adapter bracket. The weapons adapter bracket is connected to a weapon.