To capture the moment when materials change, such as during melting, solidification or crystal phase change, by in-situ X-ray diffraction measurement, the acquisition time of the X-ray diffraction images at each temperature needs to be as short as possible. OD and 1 D detectors take time to scan the detector and prepare for operation. Conventional 2D detectors also have a problem in that the X-ray shutter needs to be opened and closed between counting and reading the data. The HyPix-3000 hybrid pixel array multi-dimensional detector in 2D mode can acquire X-ray diffraction images without scanning the detector. The HyPix-3000 has two counters inside. Switching between them allows measurement without dead time. These features enable shutterless measurement of 2D X-ray diffraction images, which makes it possible to observe rapid changes in crystalline state.