We present a range-gated camera system designed for real-time (10 Hz) 3D estimation underwater. The system uses a fast-shutter CMOS sensor (1280×1024) customized to facilitate gating with 1.67 ns (18.8 cm in water) delay steps relative to the triggering of a solid-state actively Q-switched 532 nm laser. A depth estimation algorithm has been carefully designed to handle the effects of light scattering in water, i.e., forward and backward scattering. The raw range-gated signal is carefully filtered to reduce noise while preserving the signal even in the presence of unwanted backscatter. The resulting signal is proportional to the number of photons that are reflected during a small time unit (range), and objects will show up as peaks in the filtered signal. We present a peak-finding algorithm that is robust to unwanted forward scatter peaks and at the same time can pick out distant peaks that are barely higher than peaks caused by sensor and intensity noise. Super-resolution is achieved by fitting a parabola around the peak, which we show can provide depth precision below 1 cm at high signal levels. We show depth estimation results when scanning a range of 8 m (typically 1-9 m) at 10 Hz. The results are dependent on the water quality. We are capable of estimating depth at distances of over 4.5 attenuation lengths when imaging high albedo targets at low attenuation lengths, and we achieve a depth resolution (σ) ranging from 0.8 to 9 cm, depending on signal level.

Photonfocus AG in Switzerland develops and produces image sensors for automotive applications. This presentation shows the special requirements for imager chips in automobiles and gives some examples of automotive-qualified image sensors based on CMOS technology. The results point out the principal advantages of CMOS chip technology in comparison to CCD. In addition, there is an outlook for the next generation of automotive CMOS sensors. IMAGING TECHNOLOGIES IN AUTOMOBILESIn the next five years, the penetration of imaging technologies in volume production of automobiles will begin, after more than 10 years of research and development. Initial work involved imaging inside the vehicle, for applications such as driver detection and out-of-position recognition. Here the requirements on the imager are relatively modest, particularly in terms of resolution. A second and potentially more interesting field is imaging of the vehicles surroundings. Applications here can be broadly divided into two categories: those using the human eye for monitoring, and those performing automatic monitoring via image processing. Examples applications in the former category include rear view, electronic mirror, blind-spot monitoring and night vision. Examples in the second category include obstacle detection, pre-crash sensing, lane departure warning, distance measurement and traffic sign detection. These applications are at once exciting and challenging, in that the intention here is not only to give information to the driver, but for the system to intervene directly in the control of the vehicle. Typical catchwords are stop-and-go assistance, crash avoidance and adaptive cruise control. Many of the image processing techniques applicable inside the vehicle are also applicable outside the vehicle, in traffic surveillance. Examples include person and object identification and number plate recognition. Besides the usual engineering challenges of fulfilling the technical requirements at an acceptable price point, there are a number of political, social and physiological hurdles which strongly influence the penetration of imaging technologies in, and around, automobiles. REQUIREMENTS ON IMAGER CHIPS IN AUTOMOBILESOne piece at the centre of this puzzle is the electronic eye. There are several factors that speak for solid state technologies, particularly in silicon, and especially in CMOS. The main requirements upon imager chips in automotive applications include:o High reliability (automotive qualification, QS9000) o Long term availability o Low cost o High sensitivity -especially in infra-red o High speed -without blur / motion artefacts o Adequate resolution

The realm of high-speed imaging traditionally provides some of the most visually appealing images for the non-specialist. From bullets passing through objects to the minute details of animal behaviour, the ability to freeze time opens the way to unique insights into the world around us, as well as providing a valuable tool for analysis and test in an industrial environment. Often associated with high costs and complex operation, new approaches to capturing critical high-speed events are being developed which can enable scientists and engineers to use high-speed imaging as a routine tool rather than a specialist discipline. By synchronizing high-power illumination pulses with tightly controlled image sensor exposures, while at the same time providing on-board image storage and in-situ processing, a simple and flexible highspeed imaging architecture is realized, capable of wide ranging application. High-speed imaging provides unique insights into processesFrom the seminal work of Eadweard Muybridge in the late nineteenth century analysing the gait of a galloping horse [1] to the latest advances in femto-photography [2], high-speed imaging has a rich history of providing new information about motions, events, and processes. In today's industrial and scientific environments, highspeed imaging is predominately used for scientific analysis or test and measurement applications, with vehicle collision studies [3] probably the most commonly recognized. Other significant applications include particle imaging velocimetry (PIV) [4] whereby images are taken of fluid flows and particle velocities extracted as a tool for aerodynamic engineering, human motion analysis [5], as well as failure mode dynamics and analysis [6], impact testing, and ballistics research [7]. More recently, there has been increasing interest from the biological and nanotechnology sectors [8] to adapt high-speed techniques and leverage the advantages that high-speed technology brings, such as the visualization of MEMS devices.In each case it is the insight that is obtained by viewing events happening on a timescale much faster than humans are capable of visualizing, which provides the ultimate value to the user. Factors to consider for highspeed imagingHigh-speed imaging relies on the ability to capture an optical image of a scene in a short period of time. Using shorter periods of time for scene capture, generally corresponds to an increased ability to "freeze" fast moving events. It is this ability to capture short moments in time which provides the useful diagnostic information used in applications. A typical approach to capturing an image in a short period of time is to simply decrease the exposure time of the camera. Typical image sensors used within machine vision cameras have minimum exposure times in the range 5-15 microseconds, whilst dedicated high-speed imaging systems can operate with exposure times lower than 200 ns. If the object odos imaging LimitedEdinburgh, Scotland odos imaging Limited is a technology focused company specialising in th...

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