Scanning optical keyboard
First Claim
1. An optical keyboard having keys and being suitable for use with keyboard-scanning means including a plurality of switchable light sources and a plurality of light receivers, the keyboard comprising:
- a generally flat optical block having a top face and a plurality of sides, the top face being intended to cooperate with the keys;
a plurality of light injection inlets and a plurality of light detection outlets in the block respectively for coupling to the light sources and the light receivers of the keyboard-scanning means; and
a plurality of key-actuated elements and pairs of unobstructable light ducts in the block, each key-actuated element cooperating with a corresponding pair of unobstructable light ducts and being operable to selectively couple and decouple said pair of light ducts;
one of the ducts in each pair being an inlet duct connected to a light injection inlet and the other duct in each pair being an outlet duct connected to a light detection outlet in such a manner that each key-actuated element embodies an intersection of an inlet/outlet matrix in which each distinct matrix intersection is defined by a unique inlet/outlet pair, thereby making it possible for keyboard-scanning means, when used with the keyboard, to identify key depressions by applying a signal successively to each of said light injection inlets and by observing the state of all of said light detection outlets after each signal application;
said light injection inlets and said light detection outlets all being disposed along the same one of the sides of said optical block, thereby facilitating coupling between the keyboard and keyboard-scanning means.
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Accused Products
Abstract
An optical keyboard comprising: a flat optical block whose top face (9) is intended to co-operate with the keys (12); light inlets (2) and light detection outlets (3) having intersections (4) which couple one light inlet with one light detection outlet; key-actuated elements situated at the intersections for coupling or decoupling the inlets and the outlets; optical ducts which are unobstructed from a corresponding light inlet to a corresponding matrix intersection, and from a corresponding matrix intersection to a corresponding light detection outlet; and a scanning stage for applying a signal successively to each of the inlets and for observing the state of each of the outlets after each signal application; is characterized in that the light inlets and the light detection outlets are disposed along the same one of the sides (31) of said optical block, with each key emplacement being directly connected to a single light emitter and a single light receiver via respective optical ducts (2, 3).
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Citations
10 Claims
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1. An optical keyboard having keys and being suitable for use with keyboard-scanning means including a plurality of switchable light sources and a plurality of light receivers, the keyboard comprising:
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a generally flat optical block having a top face and a plurality of sides, the top face being intended to cooperate with the keys; a plurality of light injection inlets and a plurality of light detection outlets in the block respectively for coupling to the light sources and the light receivers of the keyboard-scanning means; and a plurality of key-actuated elements and pairs of unobstructable light ducts in the block, each key-actuated element cooperating with a corresponding pair of unobstructable light ducts and being operable to selectively couple and decouple said pair of light ducts; one of the ducts in each pair being an inlet duct connected to a light injection inlet and the other duct in each pair being an outlet duct connected to a light detection outlet in such a manner that each key-actuated element embodies an intersection of an inlet/outlet matrix in which each distinct matrix intersection is defined by a unique inlet/outlet pair, thereby making it possible for keyboard-scanning means, when used with the keyboard, to identify key depressions by applying a signal successively to each of said light injection inlets and by observing the state of all of said light detection outlets after each signal application; said light injection inlets and said light detection outlets all being disposed along the same one of the sides of said optical block, thereby facilitating coupling between the keyboard and keyboard-scanning means. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10)
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Specification