A low-cost high-speed CMOS camera for scientific imaging

Abstract

Non-intrusive temporally and spatially resolved measurements of dynamic phenomena are heavily reliant on high-speed (>1 kHz) digital scientific cameras. The cost of these cameras is a major constraint on the operation of many experimental and educational research facilities. In this paper we present a performance analysis of a low-cost high-speed CMOS camera, the Chronos 1.4. Developed for consumer use, we investigate its potential as a scientific camera. It uses a 12 bit Luxima LUX1310 CMOS sensor with 1280 × 1024 px at 6.6 µm pitch and 1 µs minimum global shutter. It is capable of recording at 1057 Hz at full frame and up to 38 kHz with a reduced field of view. It provides a number of features not typically found in low-cost consumer cameras, such as external triggering and shutter gating control, clock outputs, and raw binary data output. We test the linearity of the sensor response using a pulsed LED source and analyse the sensor performance in terms of noise, jitter and intensity lag. A quantitative demonstration of the camera's performance under realistic experimental conditions is demonstrated with an image correlation velocimetry measurement in a high-speed propellant spray. The camera compares favourably against several scientific high speed cameras from major manufacturers. The camera is well suited for high resolution forward-scattering and in-line imaging techniques such as schlieren, shadowgraphy, holography and bright-field microscopy. Spatial bias in the dark field noise floor makes it generally unsuitable for lowlight measurement conditions. However, the small footprint and low cost make it ideal as an educational tool and for multi-camera experiments. These tests were conducted independently of the manufacturer and the authors have no conflicts of interest to disclose.

An ecological perspective on water shedding from leaves

“…Further progress on understanding the complex interplay between leaves, rain, and wind requires a move away from laboratory studies to situations where leaves are held naturally and are subject to natural rainfall or condensation. The increasing availability of small, lightweight, and weatherproof measurement devices, affordable and powerful high-speed video cameras, and low-cost microcomputers for automated data collection make this approach more feasible than ever before ( Chan et al , 2016 ; Kwok, 2017 ; Duke et al , 2019 ; Oellermann et al , 2021 , Preprint).…”

Development of a low-cost, user-customizable, high-speed camera

“…This is demonstrated in Fig 8, where a GFP-tagged C. elegans worm was imaged with increased exposure at 30 fps with good quality. However, a vertical striping pattern becomes apparent in low light and increased gain conditions which is believed to either be a consequence of the electrical characteristics of the electronic circuitry associated with each pixel and column output amplifier [14] or due to imperfections in the image sensor power supplies and readout electronics as a similar effect was observed in the testing of the Chronos 1.4 [20]. This is slightly observable in Fig 7 with vertical line patterns, particularly in Fig 7C) which was taken at 8x analog gain.…”

“…Having a cost similar to machine vision CMOS cameras of several hundreds of dollars (USD), it also includes the added functionality and benefits usually found in more expensive standalone cameras. For instance, the Kron Technologies Inc. Chronos 1.4 camera was recently independently tested as a potential low-cost, high-speed, scientific imaging camera [20] and was reported to have beneficial features like external triggering and binary data output not found in other low-cost consumer cameras, but which our camera is also capable of. It was also found to be well suited for high resolution forward-scattering and in-line imaging like bright-field microscopy, which similarly makes biology and microscopy a key application area for our camera as well.…”

Tactile Sensing for Minimally Invasive Surgery: Conventional Methods and Potential Emerging Tactile Technologies

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