Evaluating the Image Quality of Closed Circuit Television Magnification Systems Versus a Head-mounted Display for People with Low Vision.

In this research, image analysis was used to optimize the visual output of a traditional Closed Circuit Television (CCTV) magnifying system and a head-mounted display (HMD) for people with low vision. There were two purposes: (1) To determine the benefit of using an image analysis system to customize image quality for a person with low vision, and (2) to have people with low vision evaluate a traditional CCTV magnifier and an HMD, each customized to the user's needs and preferences. A CCTV system can electronically alter images by increasing the contrast, brightness, and magnification for the visually disabled when they are reading texts and pictures. The test methods was developed to evaluate and customize a magnification system for persons with low vision. The head-mounted display with CCTV was used to obtain better depth of field and a higher modulation transfer function from the video camera. By sensing the parameters of the environment (e.g., ambient light level, etc.) and collecting the user's specific characteristics, the system could make adjustments according to the user's needs, thus allowing the visually disabled to read more efficiently.