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. 0D and 1D 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.