Patent ID: 11861897
Assignee: JIANGSU UNIVERSITY
Field: Measurement (Instruments)
Classification: CPC G  H | IPC G  H

Claim 0:
1. A portable apparatus for detecting early crop diseases based on spatial frequency domain imaging, comprising an end cover, a dark box body, a spatial frequency domain imaging apparatus, a telescopic section, and an opening-and-closing apparatus that are connected from top to bottom;
the spatial frequency domain imaging apparatus comprises a square box housing, light source modules, collimating lenses, dichroic mirrors, an achromatic lens, a first linear polarizer, a second linear polarizer, a camera, a reflector, and a digital micromirror apparatus; the collimating lenses, the dichroic mirrors, the achromatic lens, the reflector, and the digital micromirror apparatus are all mounted inside the square box housing; the light source modules are separately mounted on two adjacent side surfaces of the square box housing, the collimating lens is opposite to the light source module, and a center of the dichroic mirror is located on an axis of the collimating lens; a center of the digital micromirror apparatus is separately located on a straight line running through the center of the dichroic mirror and on an axis of the achromatic lens; a center of the reflector is separately located on the axis of the achromatic lens and on an axis of the first linear polarizer; the camera is vertically mounted at a bottom of the square box housing, and a lens passes through the square box housing and shoots downward; and the second linear polarizer is mounted in front of the lens of the camera; and
the opening-and-closing apparatus comprises sector skeletons, middle sections, and opening-and-closing skeletons, the middle section is internally connected to a light-shielding cloth, the middle section is externally connected to the sector skeleton, and each of two ends of the middle section is provided with one opening-and-closing skeleton, the light-shielding cloth is provided with an opening at the opening-and-closing skeleton, an outer circumference of the sector skeleton is provided with a guide rail for movement of the opening-and-closing skeleton; and the middle section is made of an elastic material.