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The scanning process works in the following way: a person steps inside the Intellifit cabin without undressing, the “L” shaped millimeter-waves transceiver swings around and over the person to acquire the required data. The entire scanning process lasts about 10 seconds and the collected data consists of about 200'000 points on the surface of the human body. Out of the measurements, automatic algorithms determine about 200 characteristic body sizes of the human body with an accuracy of about 6mm. 
A second technology based on other active sensors is also exploited for the measurement of the external surface of the human body. In this case, 3D cameras employ special CMOS sensors where each pixel measures the distance to the imaged surface part.
Different manufactures are present in the market. Figure 10 (right) shows the example of 3D camera of CSEM10. These cameras are based on the phase-measuring time-of-flight (TOF) principle. A light source (in this case, an array of emitting diodes) emits a near-infrared wave front that is intensity-modulated. The light is reflected by the scene and imaged by an optical lens onto the dedicated 3D-sensor. Depending on the distance of the target, the captured imaged is delayed in phase compared to the originally emitted light wave. Measuring the phase delay, the distances of the complete scene can be determined. The result of the acquisition is a depth map of the scene.
The core of such cameras is the CMOS sensor. In fact, the 3D measurement method based on TOF is integrated in the CMOS sensor. Each pixels of the sensor is constructed to measure the phase difference between the emitted light source and the captured returning light. The result are real-time 3D images of the recorded scene.
The actual CMOS technology limits the sensor size to about 25 KPixels. For this reason, to time, these sensors can be exploited only for few applications regarding the human body, as for example in security (surveillance) or automotive (recognition of pedestrians).
2.5 Digital tape measurements
As last technology available for the digital measurement of the human body, has to be mentioned a simple but effective method: the electronic tape measurement.
The method combines classical human body measurement and digital technology. The measurement process is completely similar to classical tape measurement, where lengths are measured by a tape at different keylocation of the human body (chest, waist, sleeve, etc.). The tape device records electronically the measured distances. Some devices, as for example the e-tape of E-Measurement Solutions11 showed in Figure 11, delivers the measured data to PC via wire-less. In this way, the tape measurement process results faster and simpler. 
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