A joystick for moving a cursor on a display screen uses an infrared transmitter (34) radiating into a transparent handle (14). As the handle is moved by an operator, infra-red light is directed to one of four optical detectors (31) covering up, down, left and right directions respectively. The device can also detect movement at 45 degrees to any of these directions since light is then directed to two detectors (31). A further four optical detectors (31a) are provided, each arranged adjacent one of the first four detectors (31), so that further movement of the handle in the same direction can be detected. An additional optical detector (37) is arranged to detect downward movement of the handle (14) against a spring (24). The handle is translatably mounted, rather than pivotally mounted as in a stand joystick.

This invention relates to an optical switch device including a light spot composed of a fluorescent substance in combination with radioactive elements or a pattern of a plurality of light spots and light detectors each manually moved relative to the light spots to detect a fluorescence from each fluorescent substance. An on-off pattern switching signal or a codified switching signal is obtained from an output from each light detector.

A rugged keyboard and cursor positioning device with an inherent restiveness from external fluids to interior keyboard fluid contamination. The key interrupters and cursor positioning device block optical beams for key and cursor positioning detection thus eliminating contacts and contact actuation life. When a key is in the most depressed position the key cap is against the keyboard top surface protecting all internal parts from pressure, or force from harsh use or a vandals blow.

An optical keyboard includes a plurality of photosensors arranged in an X-Y coordinate system where a plurality of rows represent a plurality of X-axes and a plurality of columns represent a plurality of Y-axes. Each sensor represents input to data processing means. When a beam of light is cast onto a photosensor, the photosensor is actuated to transmit a coded signal to a microprocessor board. The microprocessor board scans the array of photosensors row by row sequentially to identify the column position of an actuated photosensor. The input received from the scanning operation is converted to data and transmitted through either a serial or parallel interface to a computer. Interface circuitry converts the data to a form readable by the computer. Thus, by selectively moving a light source to desired photosensors, specific information can be transmitted to a computer for printout or for operation of other devices remotely controlled by the computer to permit the computer to be operated by individuals unable to perform manual keyboard operations.

A switch arrangement comprises a photoconductor to be illuminated. The switch arrangement also comprises a conductor which is intended to further transmit light escaping from the photoconductor and directed to the conductor by a local contact, wherein the conductor and the photoconductor are further under the control of an external force, arranged to move in relation to each other and to cause the development, loss or change of the contact in such a way that a detectable change is caused in the light guided through it.