A device and an algorithm for the separation of visible and near infrared signals in a monolithic silicon sensor

G. Langfelder; T. Malzbender; A. F. Longoni; F. Zaraga

doi:10.1117/12.874896

31 January 2011 A device and an algorithm for the separation of visible and near infrared signals in a monolithic silicon sensor

G. Langfelder, T. Malzbender, A. F. Longoni, F. Zaraga

Author Affiliations +

Proceedings Volume 7882, Visual Information Processing and Communication II; 788207 (2011) https://doi.org/10.1117/12.874896
Event: IS&T/SPIE Electronic Imaging, 2011, San Francisco Airport, California, United States

Abstract

The Transverse Field Detector (TFD) is a filter-less and demosaicking-less color sensitive device that easily allows the design of more than three color acquisition channels at each pixel site. The separation of light into different wavelength bands is based on the generation of transverse electric fields inside the device depleted region, and exploits the properties of the Silicon absorption coefficient. In this work we propose such a device for the joint capture of visible and near infrared (NIR) radiation, for possible applications in videoconferencing and 3D imaging. In these applications the detector is used in combination with suitably generated NIR structured light. The information of the fourth acquisition channel, mainly capturing NIR signals, can be used both for sampling NIR light intensity and for subtracting unwanted NIR crosstalk from visible channels thus avoiding the need for the IR-blocking filter. Together with the presentation of a 4-channel sensor, a suitable algorithm for the processing of signals generated in the visible and infrared bands is described. The goal of the algorithm is to minimize the crosstalk of NIR radiation inside the visible channels and, simultaneously, to maintain good color reproduction and noise performance for the sensor, while holding a good sensitivity of the NIR channel up to 900 nm. The analysis indicates that the algorithm reduces the crosstalk of infrared signals inside R, G and B channels from 31%, 12% and 5% respectively to less than 2%. Concerning noise propagation, the worst coefficient of the color conversion matrix (CCM) is -2.1, comparable to those obtained for CCM of Bayer Color Filter Arrays.

Citation Download Citation

G. Langfelder, T. Malzbender, A. F. Longoni, and F. Zaraga "A device and an algorithm for the separation of visible and near infrared signals in a monolithic silicon sensor", Proc. SPIE 7882, Visual Information Processing and Communication II, 788207 (31 January 2011); https://doi.org/10.1117/12.874896

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available