© Springer Nature Singapore Pte Ltd. 2018. Application of synchrotron radiation science to structural analysis for functional materials is attracting considerable interest. When a low-emittance synchrotron ring is used, higher performance is required from an X-ray area detector used in experiments. The charge-integrating-type detector SOPHIAS, which was designed for the SACLA free-electron laser experiments, was developed by RIKEN using silicon-on-insulator technology. The SOPHIAS detector has a 2157 × 891 pixel array consisting of 30 μm square pixels. SOPHIAS is a powerful tool for X-ray structural analysis because of its high definition and high dynamic range. The application of SOPHIAS to synchrotron radiation experiments has begun at the Photon Factory, KEK (KEK/PF). Focusing on small angle X-ray scattering (SAXS) measurements of block copolymers, synchrotron radiation X-ray experiments were conducted using SOPHIAS at KEK/PF. The SAXS pattern of a sample, polybutadiene-poly(ε-caprolactone) diblock copolymer/polybutadiene blend, has complicated peaks structure originating in Frank–Kasper σ phase; thus, the fine pixel array of SOPHIAS was very important for resolving the peaks. We report the results of experiments using SOPHIAS.