Optical media monitoring device
First Claim
1. An optical media monitoring device that detects presence of light-interrupting media between photoemitter component and a photoreceptor component of a sensor provided to operate in cooperation with each other, the optical media monitoring device comprising:
- means for driving the photoemitter component at a predetermined level of light emission;
a comparator receiving as one input thereof an output of the photoreceptor component;
means for generating a reference signal at a predetermined level, the reference signal being input to the other input to said comparator;
means for controlling said driving means to cause the photoemitter component to emit a level of light lower than a level normally used for media detection; and
means for determining the degree of dust degradation of the sensor by checking, in a state of no media present and the light emission of the photoemitter component reduced by said controlling means, whether the output of the photoreceptor component is greater than the reference signal level.
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Accused Products
Abstract
In an optical media monitoring device that detects presence of light-interrupting media between a photoemitter component and a photoreceptor component provided to operate in cooperation with each other, the photoemitter component is driven at a variable level of light emission, and a comparator compares the output of the photoreceptor component with a reference signal which is also variable. The driving means is controlled to cause the photoemitter component to emit a level of light lower than normally used for media detection. Dust degradation of the sensor is determined by checking, in a state of no media present and the reduced light emission of the photoemitter component, whether the output of the photoreceptor component is greater than the reference signal level.
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Citations
12 Claims
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1. An optical media monitoring device that detects presence of light-interrupting media between photoemitter component and a photoreceptor component of a sensor provided to operate in cooperation with each other, the optical media monitoring device comprising:
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means for driving the photoemitter component at a predetermined level of light emission; a comparator receiving as one input thereof an output of the photoreceptor component; means for generating a reference signal at a predetermined level, the reference signal being input to the other input to said comparator; means for controlling said driving means to cause the photoemitter component to emit a level of light lower than a level normally used for media detection; and means for determining the degree of dust degradation of the sensor by checking, in a state of no media present and the light emission of the photoemitter component reduced by said controlling means, whether the output of the photoreceptor component is greater than the reference signal level. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12)
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Specification