Field imaging system for hyperspectral data, 3D structural data and panchromatic image data measurement based on acousto-optic tunable filter

Abstract

The hyperspectral data and 3D structural data are highly useful in botanical research. But, the two types of information are often acquired separately and hard to be combined. In this work, a novel dual-path configuration based on acousto-optical tunable filter (AOTF) is proposed to acquire an image, structural and hyperspectral information within one acquisition process by a combination of laser triangulation. Under the configuration, the hyperspectral data and the 3D structure can be matched to subpixel level after geometrical calibration. Finally, the obtainment of 3D hyperspectral information in field experiment verifies the feasibility of this imaging system.

Experimental Analysis of Tunable Optical Spectral Imaging System Using a Grating in the Pupil Function

“…The proposed optical imaging system depicts their modification in the pupil function, a configuration that has been a widely used to encode the wavefront on the incident radiation. Phase objects are commonly used to extend the field, together with shadow objects, which are also commonly used for apodization and increased resolution of the resulting images [16,38,39]. In this work, we employ the above-mentioned method to separate the spectral images of a test object.…”

“…Angle diffractions are determined by the condition of the phase coincidence for reflections from adjacent grooves [34]; these techniques allow a specialized study of various applications in spectral image analysis, such as the diagnosis of biological samples, the classification of food or objects based on colorimetry, object segmentation, the monitoring of vegetation, and analysis of soil. [35][36][37][38][39][40][41][42][43].…”

Rapid and Precise Wavelength Determination Approach Based on Visually Patterned Integrated Narrow Bandpass Filters

“…During the combinatorial etching, the etched thicknesses of SiO 2 cavity layer were 39.2 nm, 19.6 nm and 9.8 nm, respectively. Then the top mirror stack of (HL) 6 was deposited onto the resultant cavities to form the eight narrow bandpass filters, as shown in Fig. 2(d).…”

“…Since then, spectroscopy based on prism, grating and Michelson interferometer continues to play a significant role in fields of chemistry, physics, astronomy and so on. In the past decades, some new approaches for miniature spectrometer have been developed based on various new techniques, such as acousto-optic tunable filters (AOTF) [6], integrated optical filters [7], [8], disordered photonic chip and colloidal quantum dot [9], [10].…”

Portable 4d Snapshot Hyperspectral Imager for Fastspectral and Surface Morphology Measurements

“…As 3D imaging and HSI provide two pertinent types of information related to intrinsic properties that are key metrics for substance identification and analysis, it is highly beneficial to combine spectral information with a 3D reconstructed model to a unified four-dimensional (4D) data set (x, y, z, I). Such higher-dimensional optical imaging systems, typically referred to as 4D imagers, have been studied extensively in laboratory settings [29][30][31][32][33][34]. Most previous 4D systems combine one of the HSI and one of the 3D reconstruction techniques mentioned above to achieve 4D imaging.…”