Volume 2, Issue 2

In recent years, camera-based driver assistance systems have taken an important step: from laboratory setup to series production. This tutorial gives a brief overview on the technology behind driver assistance systems, presents the most significant functionalities and focuses on the processes of developing camera-based systems for series production. We highlight the critical points which need to be addressed when camera-based driver assistance systems are sold in their thousands, worldwide – and the benefit in terms of safety which results from it.

Over the past 15 years, various interfaces on digital industrial cameras have been available on the market. This tutorial will give an overview of interfaces such as LVDS (RS644), Channel Link and Camera Link. In addition, other interfaces such as FireWire, Gigabit Ethernet, and now USB 3.0 have become more popular. Owing to their ease of use, these interfaces cover most of the market. Nevertheless, for certain applications and especially for higher bandwidths, Camera Link and CoaXPress are very useful. This tutorial will give a description of the advantages and disadvantages, comment on bandwidths, and provide recommendations on when to use which interface.

The first part of this paper describes the high dynamic range CMOS (HDRC ® ) imager – a special type of CMOS image sensor with logarithmic response. The powerful property of a high dynamic range (HDR) image acquisition is detailed by mathematical definition and measurement of the optoelectronic conversion function (OECF) of two different HDRC imagers. Specific sensor parameters will be discussed including the pixel design for the global shutter readout. The second part will give an outline on the applications and requirements of cameras for industrial safety. Equipped with HDRC global shutter sensors SafetyEYE ® is a high-performance stereo camera system for safe three-dimensional zone monitoring enabling new and more flexible solutions compared to existing safety guards.

Multi-exposure high dynamic range(HDR) imaging builds HDR radiance maps by stitching together different views of a same scene with varying exposures. Practically, this process involves converting raw sensor data into low dynamic range (LDR) images, estimate the camera response curves, and use them in order to recover the irradiance for every pixel. During the export, applying white balance settings and image stitching, which both have an influence on the color balance in the final image. In this paper, we use a calibrated quasi-monochromatic light source, an integrating sphere, and a spectrograph in order to evaluate and compare the average spectral response of the image sensor. We finally draw some conclusion about the color consistency of HDR imaging and the additional steps necessary to use multi-exposure HDR imaging as a tool to measure the physical quantities such as radiance and luminance.

With the increase in performance and decrease in cost, smart cameras have become increasingly more accessible over the past decade. Given this trend, how do you determine which smart camera best meets your needs or decide if a smart camera is appropriate for your application? Learn about the top eight considerations you do not want to forget when selecting a smart camera, including application examples and alternative solutions.

This article describes the operation and performance of global shutter pixels with correlated double sampling for CMOS image sensors. Correlated double sampling is required to keep the read noise at a level comparable to interline transfer CCDs. A pixel with voltage domain in-pixel sampling of the floating diffusion reset and signal levels is explained and its noise performance is modeled. The saturation level of this pixel is analyzed and parasitic light sensitivity is discussed. The pixel is benchmarked against other global shutter pixels that allow correlated double sampling, based upon charge domain in-pixel storage.

The applicability of broadband optical monitoring to an industrial optical coating production environment is investigated. Different monitoring strategies have been applied to the deposition of beamsplitters and longpass edge filters by electron beam evaporation without any plasma or ion assistance. While the shift and reproducibility in the optical constants were poorly specified, pure optical broadband monitoring of the coatings did not prove superior to traditional quartz crystal monitoring. On the contrary, the introduction of a hybrid monitoring strategy that combines quartz crystal and broadband optical monitoring led to significant improvements in the coating performance reproducibility compared to a pure quartz crystal monitoring approach. Accompanying computational manufacturing experiments performed for the beamsplitter design reveal the same trend.