• Proceedings of the KOSOMBE Conference
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• v.1994 no.12
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• pp.101-103
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• 1994

The film scanner that digitizes the conventional x-ray films is the necessary equipment in the transition period of going to the filmless hospital. We have developed the film scanner using laser. We have selected HeNe laser as light source. The polygonal mirror converts the point light source to line scanning light. In sensing part, the diffusing cylinder and 7 photo transistors converts the light signal which passing the film into the electric signal. With this scanner, we can scan successfully the conventional x-ray film by $1024\times1024$. Smaller the spot sire is, higher the resolution can be achieved.

• Journal of the Institute of Convergence Signal Processing
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• v.4 no.4
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• pp.15-22
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• 2003

A film scanner is one of the input devices for ac acquiring high resolution and high qualify of digital images from the existing optical film. Recently the demand of film scanners have risen for experts of image printing and editing fields. However, due to the nonlinear characteristic of light source and sensor, colors of the original film image do not correspond to the colors of the scanned image. Therefore color correction for the scanned digital image is essential in film scanner. In this paper, neural network method is applied for the color correction to CIE L/sup *//a/sup *//b/sup */ color model data converted from RGB color model data. Also a film scanner hardware with 12 bit color resolution for each R, G, B and 2400 dpi is implemented by using the TMS320C32 DSP chip and high resolution line sensor. An experimental result shows that the average color correction rate is 79.8%, which is an improvement of 43.5% than our previous method, polygonal regression method.

• Proceedings of the Korea Institute of Convergence Signal Processing
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• 2000.12a
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• pp.149-152
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• 2000

A scanner is an output device that scans documents, photographs, films etc, and convert them to digital data. Especially, a film scanner is used for scanning negative/positive films. In this paper, we design step motor control part, image sensor part, and Aか converter part which are components of the scanner and use DSP for fast signal processing. We also design the interface circuits using EPLD between these peripherals and DSP. The PC interface circuits between scanner and PC are designed by using parallel port to control and transfer the scanned data from scanner to PC. For 35mm film, we design hardwares which obtain high resolution more than 9 million pixels (horizontal resolution is 3835 and vertical resolution is 2592).

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.40 no.1
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• pp.43-50
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• 2003

Today, the demand of image acquisition systems grows as the multimedia applications go on increasing greatly. Among the systems, film scanner is one of the systems, which can acquire high quality and high resolution images. However due to the nonlinear characteristic of the light source and sensor, colors of the original film image do not correspond to the colors of the scanned image. Therefore color correction mr the scanned digital image is essential in the film scanner. In this paper, polynomial regression method is applied for the color correction to CIE $L^{*}$ $a^{*}$ $b^{*}$ color model data converted from RGB color model data. A1so a film scanner hardware with 12 bit color resolution for each R, G, B and 2400 dpi was implemented by using TMS320C32 DSP chip and high resolution line sensor. An experimental result shows that the average color difference ($\Delta$ $E^{*}$$_{ab}$ ) is reduced from13.48 to 8.46.6.6.6.6.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.18 no.1
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• pp.59-66
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• 2000

This study describes the precise DTM by image processing method through scanning the positive film of aerial photo using scanner instead of plotter. First, scanned the positive film of aerial photo by drum scanner and flatbed scanner in different resolution, and then compared the height from image processing method using auto correlation method with height which is taken using $50^m{\times}50^m$ grid in 1 :5,000 geographical map. It shows that heights from aerial photo image of high resolution obtained from scanner are comparable to the heights from 1：5,000 geographical map.

• The Journal of Information Technology
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• v.8 no.2
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• pp.53-58
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• 2005

In this study, we made experiments the preparation of silver halide microcrystals, physical ripening, chemical ripening, spectral sensitivity, additives and coating in order to develop medical laser scanner film which has photographic characteristic suitable for exposure to He-Ne and Ar laser. In the practice of sensitometry, the photographic material is exposed to a known quantity and quality of radiant energy, developed under standard conditions, and the densities resulting from the various exposures are then measured. The results are usually expressed in graphic form as curves, and from these curves numerical values are derived which are used to specify the characteristics of the material.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.4 no.2
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• pp.33-38
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• 1998

In point of flexographic printing on generally corrugated fiberboard cartons, the precision of film master and the adequate compression rate are very important factor in bar-code printing. Also, the complete system including scanner is essential for the purpose of enhancing the reading rate. The film master had good precision when the film was prepared by means of printing/developing machine after transformation of input bar-code number through transceiver, and the BWR 100 showed better compression rate than BWR 200. Also considering the bar-code reading, the complete system targeting the reading rate above 99.8% could be configured by Omni-Directional Scanner type accomplishing the reading rate above 99.5%.

• The Journal of the Korea Contents Association
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• v.8 no.11
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• pp.182-188
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• 2008

The MLC(multi leaf collimator) in charge of important role in radiation therapy field recently have been exchanging from shielding block into it rapidly, owing to being convenient. However, MLC can be occurred the leakage dose of inter_leaves and the error of algorithm in imput and output from digital signal. We compared the difference of imput method to MLC made by Varian Cop. with the error and effective field induced by MLC shaper and film scanner based on XimaVision value as using MLC layer of various shapes. According to comparing standard value with them to basic MLC layer (test1-5), MLC shaper was $0{\sim}0.29cm$, $0.23{\sim}3.59cm^2$ and film scanner was $0{\sim}0.78cm$, $0.24{\sim}3.89cm^2$. At the MLC layer to be applied in clinic, MLC shaper was $0{\sim}0.54cm$, $0.04{\sim}1.68cm^2$ and film scanner was $0{\sim}0.78cm$, $0.24{\sim}3.89cm^2$. The more distance and field from axis of central line increase, the more bigger the error value increases. There is a few mm error from standard point at the process which imput various information to apply MLC in clinic. and effective field did not have variation of monitor unit and dose owing to being a few cm2 error against real field. But there are some problem to shield critical organs because some part of target volume induced by the movement of organs can be not included, therefore we have to pay attention on the process to imput MLC layer

• 한국전자현미경학회:학술대회논문집
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• 1996.05a
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• pp.47-48
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• 1996

• Proceedings of the Korean Society of Medical Physics Conference
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• 2002.09a
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• pp.260-262
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• 2002

An accurate measurement of dose distribution is indispensable to perform radiation therapy planning. A measurement technique using a radiographic film, which is called a film dosimetry, is widely used because it is easy to obtain a dose distribution with a good special resolution. In this study, we tried to develop an analyzing system for the film dosimetry using usual office automation equipments such as a personal computer and an image scanner. A film was sandwiched between two solid water phantom blocks (30 ${\times}$ 30 ${\times}$ 15cm). The film was exposed with Cobalt-60 ${\gamma}$-ray whose beam axis was parallel to the film surface. The density distribution on the exposed film was stored in a personal computer through an image scanner (8bits) and the film density was shown as the digital value with NIH-image software. Isodose curves were obtained from the relationship between the digital value and the absorbed dose calculated from percentage depth dose and absorbed dose at the reference point. The isodose curves were also obtained using an Isodose plotter, for reference. The measurements were carried out for 31cGy (exposure time: 120seconds) and 80cGy (exposure time: 300seconds) at the reference point. While the isodose curves obtained with our system were drawn up to 60% dose range for the case of 80cGy, the isodose curves could be drawn up to 80% dose range for the case of 31cGy. Furthermore, the isodose curves almost agreed with that obtained with the isodose plotter in low dose range. However, further improvement of our system is necessary in high dose range.