Miniature three-dimensional adjusting and positioning mechanism for optical instrument

The utility model discloses a miniature three-dimensional adjusting and positioning mechanism for an optical instrument, which comprises a top plate, a middle plate and a bottom plate which are sequentially arranged from top to bottom, a through round hole is formed in the center of the top plate, a coordinate system is established on the surface of the top plate by taking the circle center of thethrough round hole as an original point and taking two vertically crossed lines passing through the original point as an X axis and a Y axis; long-strip-shaped sliding blocks A are symmetrically arranged at the two ends of the bottom face of the top plate in the X-axis direction, and protruding blocks A are symmetrically arranged in the Y-axis direction. The top surface of the middle plate is provided with a sliding groove A clamped and matched with the long-strip-shaped sliding block A, and a groove A matched with the convex block A is formed in the sliding groove A; grooves B are symmetrically formed in the bottom