A touch sensitive device is arranged with substantially parallel surfaces inside which light from a synchronized source, such as a CRT, can become trapped by total internal reflection. The screen is fitted with photodetectors which respond to the entrapment of light within the surfaces. The device i ...
The power of computer-based services is made available to telephone subscribers by a telephone station set (10) including a telephone handset (17) for audio transduction, a video output display screen (13) and manual input key facilities (16,20,23) coupled for interaction by a data processing facili ...
A light pen which includes a transparent rod at its pointing end through which light is directed to a photodetector that is fixedly positioned within the light pen. The rod is spring loaded and axially slidable in response to applied pressure, resulting in different light intensities being applied t ...
A character applying device which is controlled by a separate signal processor can be manually moved across a writing surface while the characters are being applied. A single-tipped marking instrument is moved with a prescribed motion parallel to the surface as the device is moved across the surface ...
