US Patent Application 18191824. TEMPERATURE SENSING USING OPTICAL SENSORS simplified abstract
Contents
TEMPERATURE SENSING USING OPTICAL SENSORS
Organization Name
Inventor(s)
Wegene H. Tadele of San Francisco CA (US)
TEMPERATURE SENSING USING OPTICAL SENSORS - A simplified explanation of the abstract
- This abstract for appeared for US patent application number 18191824 Titled 'TEMPERATURE SENSING USING OPTICAL SENSORS'
Simplified Explanation
This abstract discusses the use of LEDs and photodiodes on a device that comes in contact with a user for temperature sensing. By applying different bias currents to the LEDs and PDs and measuring the resulting diode base-emitter voltages, changes in voltage can be used to estimate the user's temperature. A measurement circuit with a current source or sink, amplifier, and ADC can be connected to each LED and PD to obtain these measurements. The differences in voltage measurements can then be used in equations to estimate the user's temperature.
Original Abstract Submitted
This relates to using light emitting diodes (LEDs) and/or photodiodes (PDs) on a device intended to come in contact with a user for temperature sensing. In some examples, the LEDs and PDs can be used for both biometric sensing and user temperature sensing. By biasing the LEDs and PDs with different bias currents and obtaining different diode base-emitter voltages (V) having known negative temperature coefficients, changes in V (ΔV) can be computed and used to estimate user temperature. In particular, a measurement circuit including a current source or sink, an amplifier, and an analog to digital converter (ADC) can be connected to each LED and PD. Different bias currents can be applied to the LEDs and/or PDs (the PDs being forward-biased instead of their normal reverse-biased mode for biometric sensing) to obtain different V measurements, and those differences can be used in equations to estimate the temperature of the user.
