Multispectral Camera System of UAV
Aug. 14, 2021
The images obtained through UAV photography observe ground objects in terms of spatial structure and spectral characteristics. UAV with Multispectral Camera System flexibly provides more effective information. It has advantages and capacities in remote sensing applications such as crop growth, environmental protection, and geological disaster assessment.
Imaging Principle of Multispectral cameras
Through spectroscopic technology, multispectral cameras obtain information about the radiation or reflection of ground objects in multiple spectrum bands. The method of light splitting determines the structure and volume of multispectral cameras, and its data processing method. At present, light splitting methods of multispectral cameras are mainly divided into optical path splitting type, filter wheel type and multi-lens type.
Optical path splitting type multispectral camera
Optical path splitting type multispectral cameras let the light pass through a lens. The light of the target was dispersed to different wavelengths through an optical prism or optical grating. Then the light in different wavelengths is focused on different positions of the detector through a converging optical system.
The light splitting in this way mainly uses optical prisms and optical gratings to split light. Optical prisms split light because different wavelengths of light have different refractive indexes in the medium. The light entering the optical prism passes through the different refractive indexes. Then it is finally projected onto the detectors at different positions.
The advantages of light splitting with prism are high efficiency. There is no problem with spectral level overlap. But the prism is nonlinear to the spectrum dispersion. The performance of light splitting with optical prisms is better than the infrared range in the ultraviolet range due to the limitation of the material.
The light splitting with optical prisms can be applied to agriculture and forestry, environmental assessment, coastline management, and wetland research.
Filter wheel type multispectral camera
The imaging principle of filter wheel type multispectral cameras is to properly synchronize the frequency of sensor sampling and filter rotation, so that every time the filter rotation is turned to an optical filter, the image can be imaged on the sensor. The filters of filter wheel type multispectral cameras can be replaced. It is free to choose the band and channel number. The light path is simple.
Narrowband spectroscopic type multispectral cameras
A plurality of independent filter substrates is successively spliced into a filter array. Then the filter array is placed in front of the imaging lenses. After the light is split by the filter array. The multi-band light is dispersed to different positions of the detector. Images of the corresponding band are obtained in different areas on the detector. Images of different bands in different regions can be obtained for each exposure. The same regional multi-spectral image is obtained in the end.
CLZ Precision Optics Co., Ltd. provide you with all kinds of optical components required for multispectral cameras, including spherical lenses (plano-convex lenses, double-convex lenses, cemented lenses, etc.), optical filters and optical prisms. With sophisticated instruments and superb processing skills, we will provide you with high-quality optical components. We sincerely invite you to discuss detailed product information with us, please contact firstname.lastname@example.org.