IMAGING PLATE ST-V AND LARGE IP READER IPR4080. N. Sakabe, N. Watanabe¹, M. Suzuki¹, J. Miyahara², K. Sasaki³ & K. Sakabe⁴, Institute of Applied Biochemistry, University of Tsukuba, Tsukuba, Ibaraki, 306 Japan, ¹PF, KKK. Tsukuba, Ibaraki, 305 Japan, ²Fuji Photo FiLm Co. Ltd, Miyanodai, R&D Center, Ashigarakamigouri, Kanagawa, 258 Japan, ³College of Medical Technology, Nagoya Univ.Higashi, Nagoya, 461 Japan, ⁴Dep. of Chem. Nagoya Univ., Chikusa, Nagoya, 464 Japan

Imaging plate (IP) is one of the best detector for X-ray crystal analysis. It is necessarily to keep sample to detector distance large to get large signal/background noise ratio. This means the size of IP must be larger the better, however, the size is limited by many reasons such as availability of hand Ling, IP readers. The other important nature of IP is sensitivity, dynamic range and spatial resolution, and so on. In the PF, we have used the 400x200mm size of BASm type of IP with BA100 and BAS2000 as the readers for protein crystallography. Recently we have examine ST-V type of IP and get good resuLts. The imaging plate ST-V gives 20% high S/N ratio at wavelength being 0.7A in S/N ratio in comparison with that of BASm. An image reader(IPR4080) for Large IP (400x800mm) has been developed. Dynamic range of this IPR4080 is 10⁵ order. Sensitivity is very similar to that of BA100; two X-ray photons can be detectable.