Visible-Band Nanosecond Pulsed Laser Damage Thresholds of Silicon 2D Imaging Arrays

Abstract

Laser-induced camera damage thresholds were measured for several sensors of three different sensor architectures using a Q-switched Nd:YAG laser in order to determine their pulsed laser-induced damage thresholds. Charge coupled device (CCD), front-side illuminated complimentary metal-oxide semiconductor (FSI CMOS), and back-side illuminated (BSI) CMOS sensors were assessed under laboratory and outdoor environments by increasing the focused laser intensity onto the sensors and recording the sensor output. The damage sites were classified qualitatively into damage types, and pixel counting methods were applied to quantitatively plot damage scale against laser intensity. Probit-fits were applied to find the intensity values where a 95% probability of damage would occur (FD95) and showed that FD95 was approximately the same under laboratory conditions for CCD, FSI CMOS, and BSI CMOS sensors (mean 532 nm FD95 of 0.077 ± 0.01 Jcm−2). BSI CMOS sensors were the most robust to large-scale damage effects—BSI sensor kill was found at approximately 103 Jcm−2, compared to 10 Jcm−2 for FSI CMOS, and between ~1.6 and 2.7 Jcm−2 for CCDs.

Laser safety for electro-optical imaging systems: exposure limits and hazard distances

“…To derive damage-related laser safety quantities for electro-optical imaging systems analogous to those of the human eye (EL MPE and hazard distance NOHD), we had to start from the laserinduced damage threshold (LIDT) of the image sensor, which is located at the focal plane of the camera lens. Such damage thresholds for imaging sensors are usually not known and have to be determined by appropriate measurements, e.g., see the work of Becker et al, 13,14 Théberge et al, 15 Burgess et al, 16 Westgate and James, 17 and Schwarz et al [18][19][20] In the next step, we had to transfer the image sensor's damage threshold to the corresponding value at the position of the camera lens' entrance aperture to achieve Objective 1. However, this required finding out how the irradiance distribution of the threatening laser beam is related to the irradiance distribution in the focal plane of the camera lens.…”

An approach for laser safety calculations for electro-optical imaging systems

“…Such damage thresholds for imaging sensors are usually not known and have to be determined by appropriate measurements, e.g., see the work of BECKER et. al [12,13], THÉBERGE et al [14], BURGESS et al [15], WESTGATE et al [16] and SCHWARZ et al [17][18][19]. In the next step, we had to transfer the image sensor's damage threshold to the corresponding value at the position of the camera lens' entrance aperture in order to achieve Objective 1.…”

“…Publications related to measured cw-laser induced damage thresholds (LIDT) of CCD and CMOS cameras are, for example, BECKER et. al [12,13], THÉBERGE et al [14], BURGESS et al [15], WESTGATE et al [16] and SCHWARZ et al [17][18][19] Here, we refer to the last-mentioned publication by Schwarz et al and summarize these threshold values in Table 3. Please note that SCHWARZ measured these values for specific image sensors (CCD sensor: Sony ICX098, CMOS sensor: Aptina MT9V024).…”

Long-range nanosecond pulsed laser damage of CMOS cameras

“…The measurement of laser-induced damage thresholds of imaging sensors is an important and ongoing topic in recent year, for the aim of better understanding the sensor vulnerability to laser hazards and threats, as well as improving the design for the high energy laser weapons in battlespace particularly UAVs, snipers, and imaging infrared seekers on missiles, etc. A fruitful work have analyzed the laser damage effect and laser induced damage thresholds on various types of optical sensors over several decades, either numerically or experimentally, including complementary metal-oxidesemiconductors (CMOS) detector 1,2 , silicon-based camera 3,4 , charge-coupled devices (CCD) cameras 1,2,5 , positiveintrinsic-negative (PIN) photodiode 6 , digital micromirror device (DMD) 7,8 , with different laser pulse width 7,9 or wavelength bands 3,10 . In general, these laboratory research primarily answer the question: if one has a known sensor and several known laser parameters, what laser fluence can damage the camera.…”