Detector shield
First Claim
1. A photodiode detector shield for use in a physiological sensor, said shield comprising:
- a first layer of a detector shield comprising an electrically conductive material, said first layer including an optically transmissive area;
a second layer of said detector shield comprising a material which reflects light of a predetermined band of wavelengths substantially evenly throughout the predetermined band;
a faraday cage;
said second layer comprising at least a portion of an outer layer of said cage;
wherein said second layer combines with said first layer to substantially reduces light from contacting said first layer during optical measurements.
3 Assignments
0 Petitions
Accused Products
Abstract
An improved photodiode detector shielding apparatus and method are provided which shield a photodiode detector from electromagnetic interference and ambient light, without affecting the wavelengths of light that reach the photodiode. The improved photodiode detector shield has two layers. A bottom layer is substantially made from an electrically conducting material and is fixed over a photodiode in order to shield it from EMI and ambient light. A top layer is substantially made from a lustrous, shiny, reflective material that reflects an equal amount of light across a band of wavelengths. Both layers have areas with optically transmissive openings, which are aligned to allow for the unobstructed passage of light of a band of wavelengths to the photodiode. Light within a band of wavelengths is evenly reflected off the top of the first surface and also reaches the photodiode. In this regard, the detector shield blocks EMI and ambient light without affecting the wavelengths of light desired to reach the photodiode.
841 Citations
16 Claims
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1. A photodiode detector shield for use in a physiological sensor, said shield comprising:
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a first layer of a detector shield comprising an electrically conductive material, said first layer including an optically transmissive area; a second layer of said detector shield comprising a material which reflects light of a predetermined band of wavelengths substantially evenly throughout the predetermined band; a faraday cage;
said second layer comprising at least a portion of an outer layer of said cage;wherein said second layer combines with said first layer to substantially reduces light from contacting said first layer during optical measurements. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10)
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11. A method of assembling an improved detector for use in a physiological sensor, said method comprising:
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providing a first layer of a detector shield, said first layer comprising a conductive material configured to block electromagnetic interference; providing a second layer of a detector shield, said second layer comprising a lustrous material that substantially evenly reflects various wavelengths of incident light; providing a faraday cage, said second layer comprising at least a portion of an outer layer of said cage; at least partially covering said first layer with said second layer; at least partially covering a photodiode with said first and second layers. - View Dependent Claims (12, 13, 14, 15)
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16. A photodiode detector shield for use in a physiological sensor, said shield comprising:
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a first layer of a detector shield comprising an electrically conductive material, said first layer comprising an optically transmissive area; a layering means for at least partially covering said first layer, said layering means configured to reflect a predetermined band of wavelength substantially evenly throughout the predetermined band, said layering means comprising an optically transmissive area; and a faraday cage, said layering means comprising at least a portion of an outer layer of said cage.
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Specification