A high dynamic range (HDR) monitor is a computer monitor capable of rendering a higher dynamic range, also called a luminance ratio, than a conventional monitor. Dynamic range is the luminance ratio between the darkest of the dark aspects of a picture displayed on a computer screen and the brightest of the bright aspects that the monitor can reproduce. Essentially, a high dynamic range monitor is able to present a higher luminance ratio between the aspects, bringing out far more of the darker details, most of which will ordinarily be overwhelmed by brightness. The high dynamic range monitor is able to compensate for the overwhelming brightness to show a vastly more realistically lighted image.
Luminance ratio is measured on a logarithmic scale designated candela/m2. A candela is the brightness produced by one candle and m2 is a square-meter. The human eye has a dynamic range, also called a luminance or brightness ratio, of approximately 1,000,000:1. A starlit scene has a photometer-captured dynamic range of 0.001 candela/m2 (cd/m2); a sunlit scene, a dynamic range of 100,000 cd/m2, which is millions of times higher. A high dynamic range monitor will capture more of the luminance for a more precise projection of this dynamic range.
High dynamic range monitors have been developed to present nearly absolute blackness and higher levels of brightness, almost 3½ times brighter than what is ordinarily achieved on a conventional monitor, which can present only about 600:1 cd/m2. A high dynamic range monitor is capable of some 200,000:1 cd/m2. Conventional monitors cannot present absolute blackness simply by virtue of the residual brightness of the screen that is inherent in its being turned on. A high dynamic range monitor will present true blackness and a less overwhelming brightness as a result of technology that modifies a liquid crystal display (LCD) cathode ray tube using a modulated series of light emitting diodes (LED). Thus a picture on a high dynamic range monitor is closer to what the eye would register at the scene of what is pictured. A high dynamic range monitor presently costs some $49,000.
Development of the high dynamic range monitor is one result of the advent of the ubiquitous digital camera. A composite technique, whereby three pictures are shot of the same scene at varying exposure levels, was developed and captures and displays a higher dynamic range in a digitalized image. The higher dynamic range image can then be displayed on a conventional monitor.
