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Research paper : Development of a real-time all-in-focus microscope (K. Ohba)−242−Synthesiology - English edition Vol.2 No.4 (2010) implementation to increase the memory capacity became necessary. Here, implementation of the sequential processing described earlier reduced the memory volume. As a result, processing could be accomplished within the internal memory of the FPGA, and target specification of 30 frames/sec. was achieved.Figure 17 shows the examples of output images using Prototype 2. They look the same as the ones shown for Prototype 1, but actually, the all-in-focus images shown on the left and the depth images shown on the right are moving images. Eight focal points were recorded per frame, and as the performance of Prototype 1 was 0.5 frame/sec. while that of Prototype 2 was 30 frames/sec., the processing speed of the latter was 60 times faster.6 Third FS phaseWith the developments up to this point, the following points became apparent.・ By using the existing camerahead of high-speed cameras and LVDS, image capture, communication, and processing could be separated, and high-speed parallel processing using general FPGA was possible for the processing part.・ Mechanical focal distance movement could be done using varifocal lens.From the talks with the company, while utilizing the high-speed processing part, we decided to specialize in the microscope use that had the highest potential in terms of business application. However, for the mechanical focal distance movement, the second item mentioned above, the varifocal lens could not be used due to precision issues. Here, I shall explain the development of the system specifically for microscope use in the third FS phase.For the mechanism for moving the focal distance in the microscope system, we used the commercially available focal distance movement mechanism PZT actuator P-721 and 20 and driver E-612, C0 from PI Polytec Inc. By attaching these between the objective lens of the microscope, they enable parallel movement of the objective lens for 0-100 m. The reason for not using the varifocal lens used in the prototypes of chapters 4 and 5 was because in the varifocal lens, the f value of the lens itself was changed by changing the thickness of the lens. Therefore strictly speaking, images of different magnifications were composited, and this was not appropriate for producing high precision all-in-focus images.Fig. 17 Example of output by Prototype 2.Fig. 18 External appearance of microscope system.Fig. 19 Example of typical microscope image.(a) All-in-focus image 1(c) All-in-focus image 2(b) Depth image 1(d) Depth image 20 µm10 µm20 µm30 µm40 µm50 µm60 µm70 µm80 µm90 µm

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