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 1.4. Developed for consumer use, we investigate its potential as a scientific camera. It uses a 12 bit CMOS sensor with px at 6.6 pitch and 1 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 low-light 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.