Plant detection systems comprising a photodetector housing with a detector lens and an aperture plate

A plant detection system, comprising:

• a radiation module configured to emit a beam of radiation;
• and
• a photodetector system comprising:
• a photodetector housing having sidewalls forming a cylindrical shape therebetween;
• one or more photodetectors disposed near a first end of the cylindrical shape, the one or more photodetectors configured to receive reflected portions of the beam of radiation and generate an electrical signal based on the received portions of the beam of radiation;
• a detector lens disposed near a second end of the cylindrical shape opposite the first end, the detector lens configured to direct the reflected portions of the beam onto at least one of the one or more photodetectors;
• and
• an aperture plate disposed within the photodetector housing between the detector lens and the one or more photodetectors and having an aperture extending therethrough, a surface of the aperture plate facing the detector lens extending between the sidewalls of the photodetector housing so that at least some outer edges of the aperture plate are adjacent to the sidewalls of the photodetector housing.

A plant detection system, comprising:

• a radiation module configured to emit a beam of radiation;
• and
• a photodetector system comprising:
• a photodetector housing having sidewalls extending between a first end of a housing and a second end of the housing;
• one or more photodetectors disposed near a first end of the housing, the one or more photodetectors configured to receive reflected portions of the beam of radiation and generate an electrical signal based on the received portions of the beam of radiation;
• a detector lens disposed near a second end of the housing opposite the first end, the detector lens configured to direct the reflected portions of the beam onto at least one of the one or more photodetectors;
• and
• an aperture plate disposed within the photodetector housing between the detector lens and the one or more photodetectors and having an aperture extending therethrough, the detector lens and the aperture plate configured so that stray radiation received by the detector lens is directed through the aperture in the aperture plate or onto a surface of the aperture plate without being directed onto the sidewalls of the photodetector housing.