Abstract: Disclosed are a derivative of a 2,5-diketopiperazine compound, and a preparation method therefor, a pharmaceutical composition thereof and the use thereof. Specifically, disclosed are a compound as represented by formula (I), a stereoisomer thereof, a tautomer thereof or a pharmaceutically acceptable salt thereof, or a solvate of any one of the aforementioned. The compound is new in terms of structure, and has good anti-tumor activity and water solubility.

Abstract: Provided are an optical fingerprint apparatus and an electronic device, the optical fingerprint apparatus includes: a light directing layer configured to direct a light signal returned from a finger above the display screen to an optical sensing array along at least two directions, where the at least two directions are oblique with respect to the display screen, and projections of the at least two directions on the display screen are at different angles with a polarization direction of the display screen; and the optical sensing array including a plurality of sensing unit groups, where light signals in the at least two directions are used to obtain a fingerprint image of the finger, and a difference between the light signals in the at least two directions received by the sensing unit group is used to determine whether the finger is a real finger.

Abstract: Provided are an optical fingerprint apparatus and an electronic device, the optical fingerprint apparatus includes: a light directing layer configured to direct a light signal returned from a finger above the display screen to an optical sensing array along at least two directions, where the at least two directions are oblique with respect to the display screen, and projections of the at least two directions on the display screen are at different angles with a polarization direction of the display screen; and the optical sensing array including a plurality of sensing unit groups, where light signals in the at least two directions are used to obtain a fingerprint image of the finger, and a difference between the light signals in the at least two directions received by the sensing unit group is used to determine whether the finger is a real finger.