Photocurrent measurement through frequency domain analysis

Derrick Chee Chiang Tiew, Ye Chow Kuang

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This paper presents the technique of using the frequency response function statistics of a photosensor to perform indirect light intensity measurement. Both random phase multisine and Gaussian noise source were designed as the excitation signals to the photodetector circuit. A miniature solar cell was used to provide the photo-generated current in tandem with different light irradiance from a LED light bulb with brightness control. The results show that the standard deviation of the frequency response function is a monotonic function of the photo-generated currents. Larger current (or light intensity) produces larger standard deviation. This promising result provides an indirect method to measure the photo response of optical sensors especially those sensors that produce minute photocurrent, thus avoiding environmental interference faced in wide-band direct current measurement technique.
Original languageEnglish
Title of host publicationProceedings of the 2015 IEEE International Instrumentation and Measurement Technology Conference
EditorsMarcantonio Catelani
Place of PublicationNew Jersey USA
PublisherIEEE, Institute of Electrical and Electronics Engineers
Pages440 - 445
Number of pages6
ISBN (Print)9781479961139
Publication statusPublished - 2015
EventIEEE International Instrumentation and Measurement Technology Conference 2015 - Pisa, Italy
Duration: 11 May 201514 May 2015
Conference number: 32nd (Proceedings)


ConferenceIEEE International Instrumentation and Measurement Technology Conference 2015
Abbreviated titleI2MTC 2015
OtherTheme: The "Measureable" of Tomorrow: Providing a Better Perspective on Complex Systems
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