초록 ▼

In an optoelectronic circuit element for effecting a manually controlled output signal comprising at least one radiation-emitting element, a radiation-propagating unit and at least one radiation-sensitive element, the radiation-propagating unit being a solid body which is transparent to the radiatio

In an optoelectronic circuit element for effecting a manually controlled output signal comprising at least one radiation-emitting element, a radiation-propagating unit and at least one radiation-sensitive element, the radiation-propagating unit being a solid body which is transparent to the radiation in question and which has an interface which is exposed to radiation from the radiation-propagating unit, an identifiable change in the state of the radiation-sensitive element is effected by changes in the conditions for total internal reflection of the radiation at the interface arising from contact of an actuating body, say a finger, with said interface.

대표청구항 ▼

An optoelectronic circuit element, particularly a touch key, for effecting a manually controlled output signal comprising at least one radiation-emitting element, a radiation-propagating unit, and at least one radiation-sensitive element, where the radiation-emitting element is arranged to transmit

An optoelectronic circuit element, particularly a touch key, for effecting a manually controlled output signal comprising at least one radiation-emitting element, a radiation-propagating unit, and at least one radiation-sensitive element, where the radiation-emitting element is arranged to transmit radiation via the radiation-propagating unit to the radiation-sensitive element and the two elements are so positioned in relation to said unit that an identifiable change in the state of the radiation-sensitive element can be induced by means of an external actuating body, preferably a fingertip, wherein the radiation-propagating unit is a solid body, transparent to the radiation used, having a touch surface which is the interface between an optically tenuous, external medium, usually air, and an optically denser medium, preferably glass, in the unit and which surface is exposed to radiation from the radiation-emitting element, wherein said identifiable change in the state of the radiation-sensitive element is induced only when the actuating body is applied in direct contact with said touch surface of the radiation-propagating unit and effected by the change in the conditions for total internal reflection of the radiation at the touch surface on contact, and wherein with respect to the critical angle for total internal reflection at the touch surface, only the radiation transmitted from the radiation-emitting element via the touch surface itself is used for the function of the circuit element, stray radiation penetrating through the touch surface from external sources, or radiation reflected in the actuating body when this body is not in direct contact with the touch surface, being unable to reach the radiation-sensitive element either directly or via refractions or reflections at the interfaces of the radiation-propagating unit.