Advertising and marketing displays often consist of non-static images, such as video images and other digital displays. For example, large-scale digital displays are widely used in major urban centers, as well as in stadiums, arenas, exterior walls of buildings and other applications. There exists an increasing need for smaller scale displays that are capable of displaying a static or dynamic video image so as to better attract the attention of onlookers. Displays of this nature may be used for advertising, public service information, and the like. As used in this patent specification, the terms “video display” or “flat panel display” encompasses any type of image display, whether for commercial advertising or other purposes. Preferably, such a display is a digital static or dynamic video display, but other video display types are known.
There is a need to provide video display systems that are suitable for use as a street or floor-level display for use in a harsh environment, such as outdoor use in locations where the units may be exposed to direct sun, and other situations of extreme heat or cold. Flat panel display screens, such as LCD panels, provide a high degree of resolution and are well-suited for displaying advertising and other images on a smaller scale, for example street-level displays. As well, advances in LCD and other flat panel screen technologies have permitted very bright display capabilities, making this technology in principal suitable for outdoor use in direct or near-direct sunlight. However, apart from certain closely monitored environments such as airports and retail stores, exposed video units can be exposed to vandalism and theft. As well, outdoor use of an exposed screen is usually difficult as a result of exposure to moisture and extreme temperature conditions. One solution is to enclose a video screen within a housing or enclosure. An enclosure may also find uses in indoor settings, where for security or other reasons it is desired to encase the video display unit within a robust enclosure.
Conventional LCD monitors are suitable for operation in a temperature range of approximately 5° C. to 40° C. At temperatures above this range, the screen may not function and may be temporarily or permanently damaged, while below this range the display may also not function properly. This presents a drawback for outdoor usage of LCD displays (and other flat panel digital monitors) that are enclosed within a housing, since temperatures can exceed this range. The interior of such an enclosure can experience a greatly elevated temperature, resulting from the combination of internally-generated heat from the video monitor, as well as absorbing of heat from the sun. There is therefore a need to provide a system which includes a secure enclosure for a flat panel digital display unit, but which is capable of maintaining a suitable temperature range for a video unit. Thermal management of the system should be provided in a manner which is efficient, reasonably quiet and reliable within a range of conditions.