 Image Number 3 for United States Patent #6525677.
An optical laser numeric keypad (100) provides a digital signal indicative of which of a plurality of key locations is selected. The optical laser numeric keypad (100) comprises a plurality of optical sensors (132 and 134) each configured to respond to a change in a received light quantity and to provide an electrical signal in response to a selection of a key at a key location. The received light quantity of at least one of the plurality of optical sensors (132 and 134) is changeable by selection of a key location.
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