With the widespread use of computers and word processing systems in the workplace, there has been an increased concern over the ergonomics of these devices. Where an operator must spend long periods of time viewing a video display monitor, often without relief, it is paramount that the monitor be designed to provide a high level of operator comfort and convenience in its use. Most notably, it has been recognized that display monitors should provide for the ergonomical differences between operators and for differences in the environments in which these devices are used. Since one standard cannot suit all, display monitors must be adjustable to suit the needs of the individual operator in his individual working environment.
More specifically, for an operator using a video display monitor, varying lighting conditions in the workplace produce light reflections and glare which may in turn cause eyestrain and other detriments. To solve this problem it is desirable that the individual operator be able to adjust the tilt angle of the display monitor a few degrees forward and back in order to control glare from the screen and to achieve an optimum viewing angle. It is further desirable that the tilt angle be quickly and easily changed and that the new tilt angle be maintained with a minumum of hand operated locking devices. The prior art has addressed these problems in numerous ways.
One solution has been the tilt and rotate ball. An example of this apparatus is disclosed in U.S. Pat. No. 4,365,779 issued to Bates et al. The display monitor is supported on a stationary base by means of a spherical ball and socket joint which permits tilting and rotating of the monitor with respect to the base.
A very different design for a tilting monitor is disclosed in U.S. Pat. No. 4,368,867 issued to Pendleton et al. a display monitor has two pairs of elongated feet suspended from its bottom. The feet rest on the inclined surfaces of a pair of parallel, trapazodial shaped base members joined together by a horizontal plate. The trapazodial base members have step-like indentations on their inclined surfaces, for holding the elongated feet, which correspond to the desired viewing angles. To change viewing angles, the monitor is moved incrementally up the step-like indententation, basically in an arc.
Still another approach for varying the tilt angle of a display monitor is disclosed in U.S. Pat. No. 4,372,515 issued to Noonan. In this patent, a display monitor housing is mounted to a stationary pedestal base by means of a rack and spur gear arrangement, which allows a tilting movement of the monitor with respect to the pedestal base. This apparently allows the center of gravity of the monitor to be co-located with its contact point on the pedestal base to thereby balance the monitor on the base.
Devices such as those discussed above are basically effective, although they suffer from certain disadvantages. All devices of this type generally include a base or pedestal support and some complex mechanism for mounting the display monitor thereon. This often results in a very expensive assembly which is bulky on an operator's desk. Some of the devices include detents which allow a tilt adjustment only in predefined increments or steps, rather than continuously throughout a tilt range, as would be more desirable. Many of the devices require the movement of the entire weight of the monitor to accomplish tilting. Still others require locking devices to keep the display monitor stationary once the tilt angle is set.