Optical Molecular Imaging (OMI) has the advantages of high sensitivity, low cost and ease of use. By labeling the regions of interest with fluorescent or bioluminescence probes, OMI can noninvasively obtain the distribution of the probes in vivo, which play the key role in cancer research, pharmacokinetics and other biological studies. In preclinical and clinical application, the image depth, resolution and sensitivity are the key factors for researchers to use OMI. In this paper, we report a high sensitivity optical molecular imaging system developed by our group, which can improve the imaging depth in phantom to nearly 5cm, high resolution at 2cm depth, and high image sensitivity. To validate the performance of the system, special designed phantom experiments and weak light detection experiment were implemented. The results shows that cooperated with high performance electron-multiplying charge coupled device (EMCCD) camera, precision design of light path system and high efficient image techniques, our OMI system can simultaneously collect the light-emitted signals generated by fluorescence molecular imaging, bioluminescence imaging, Cherenkov luminance and other optical imaging modality, and observe the internal distribution of light-emitting agents fast and accurately.
With the unceasing speedup of the train in China, traffic safety has been closely related to people’s livelihood. As elements that determine the reliability and safety in railway traffic, wheel set must be detected with much accuracy. Based on scanning method, a portable measuring system for measuring profile of train wheels is presented in this paper. Scanning part, which is pulled manually, consists of an 1-D laser sensor, whose accuracy reaches 0.05mm, and a magnetic grid sensor, whose solution reaches 0.05mm. Every 0.05mm of magnetic head movement will make the 1- D laser sensor send its current data to the tablets to get the wheel profile. The geometrical parameters, including flange thickness, flange height, rim width and QR (which is representative of vertical wear) can be calculated once the scanning is done. The systematic errors and the random errors have been analyzed in this paper. After the error compensation, the repeatability error is below 0.05mm, and the measurement accuracy of each parameter is below 0.1mm.