Optically activated keyboard for digital system having character back lighting
First Claim
1. A keyboard for a manual input apparatus having plural key means comprising:
- (a) plural key means, each key means including;
a key cap having a light transmissive portion extending to a surface thereof;
(b) a light transmissive plunger having an axis extending through said key cap and secured to said key cap;
(c) a pair of intersecting wave guides disposed normal to the axis of said plunger, said plunger having a light reflective portion projectable into said wave guides at their location of intersection; and
(d) light generating means disposed at an end portion of one of said intersecting wave guides for transmitting light along said one wave guide toward said intersection,(e) said plunger responsive to a predetermined condition to deflect said light along the other of said intersecting wave guides and responsive to said light from said light generating means to transmit said light to said surface of said key cap to provide a predetermined symbol representation at said surface.
1 Assignment
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Accused Products
Abstract
An optically activated keyboard having key members, each with a key pad having illuminated symbols at the keypad surface and for contact with the finger of the operator. A plunger is secured to the key pad for operating a device to indicate which key has been depressed. In one embodiment of the present invention, the plunger is formed of light transmitting material to transmit light from the interior of the keyboard to the key pad. The key pad has a light transmissive portion with a symbol thereon which is illuminated by the light passing through the plunger to provide the desired illuminated symbol. As a second embodiment, the symbol can be disposed in the light conducting plunger or therebeneath whereby the light entering the transparent key pad is in the shape of the desired symbol in either a negative or a positive representation thereof to project the desired symbol from the key pad. As a third embodiment, light travelling in the optically activated keyboard wave guides is partially reflected into the transparent plunger by a beam splitter in the plunger end extending into the wave guide. As a fourth embodiment, the beam splitter of the third embodiment is a portion of the plunger and extends below the wave guide to a light source. As a fifth embodiment, a slot is provided between the light source and the plunger for receipt of a removable template containing the characters corresponding to the key configuration.
170 Citations
25 Claims
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1. A keyboard for a manual input apparatus having plural key means comprising:
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(a) plural key means, each key means including;
a key cap having a light transmissive portion extending to a surface thereof;(b) a light transmissive plunger having an axis extending through said key cap and secured to said key cap; (c) a pair of intersecting wave guides disposed normal to the axis of said plunger, said plunger having a light reflective portion projectable into said wave guides at their location of intersection; and (d) light generating means disposed at an end portion of one of said intersecting wave guides for transmitting light along said one wave guide toward said intersection, (e) said plunger responsive to a predetermined condition to deflect said light along the other of said intersecting wave guides and responsive to said light from said light generating means to transmit said light to said surface of said key cap to provide a predetermined symbol representation at said surface. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25)
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Specification