Abstract: Fiber optic plate is widely used in fields such as low-light level night vision, space detection, nuclear diagnosis, medical diagnosis and treatment, and has certain requirements for strength in application. However, there is currently a lack of relevant research. In this paper, the effect of melt-pressing temperature on the bending strength of fiber optic plate in x, y, and z directions by three point bengding method was studied. When the melt-pressing temperature is 660 ℃, the secondary multi-fiber fusion is insufficient, leading to gaps. The bending strength of fiber optic plate is low, with values in x, y and z directions of 107, 93 and 114 MPa, respectively. As the melt-pressing temperature increases, the gap between the secondary multi-fiber disappears at 670 ℃, but there is still an interface, and the bending strength is improved, with values in x, y and z directions of 110, 109 and 125 MPa, respectively. At the melt-pressing temperature of 680 ℃, the secondary multi-fiber is fully fused, and the bending strength of fiber optic plate meets the rule of mixture of composite in x and z directions, which is 123 and 127 MPa, respectively. Meanwhile, the core glass in y direction plays a reinforcing role to the cladding glass, and the bending strength is 113 MPa. This study is of great significance in improving the strength of fiber optic plate to meet the requirements of installation and use.

Key words: fiber optic plate, melt-pressing temperature, bending strength, rule of mixture, secondary multi-fiber, interface