sg 3151-u  (SphereOptics GmbH)

Journal: Journal of Biomedical Optics

Article Title: Spectral analysis comparison of pushbroom and snapshot hyperspectral cameras for in vivo brain tissues and chromophore identification

doi: 10.1117/1.JBO.29.9.093510

Figure Lengend Snippet: Normalized reflectance spectral responses when the zenith polymer reflectance standard was illuminated with different sensors. The spectrometer measurement was conducted with a fiber optic positioned orthogonally to the polymer reference at a distance of 5 cm. The HS camera measurements were obtained by capturing a scene of the polymer at ∼ 40.5 cm distance, utilizing an ROI of 25 × 25 pixels . The responses from the HS cameras represent the mean spectral signatures of the polymer pixels in the ROI, with their corresponding standard deviation, as indicated by the shaded color between the mean and the corresponding data points. The spectrometer employs 1913 bands and encompasses the 400 to 925 nm spectrum. The HS linescan VNIR camera covers the 400 to 1000 nm spectral range using 369 bands. Finally, the HS snapshot NIR camera spectrum range covers from 660 to 950 nm using 25 bands. The Pearson correlation coefficient is presented after comparing the measured bands of each sensor with the polymer reference response.

Article Snippet: Equation (1) eliminates the effect of the HS sensor and the lighting conditions captured with the raw images to obtain the reflectance information R from the sample, R = I raw − I dark I white − I dark , (1) where I raw is the captured raw data of the sample, I dark is the raw dark reference captured with the lens cap in front of the camera lens, and I white is the raw white reference intensity reflected over a Lambertian diffuse target with 95% of reflectance values (SG 3151-U, SphereOptics GmbH, Herrsching am Ammersee, Germany).

Techniques: Polymer, Standard Deviation

Journal: Journal of Biomedical Optics

Article Title: Spectral analysis comparison of pushbroom and snapshot hyperspectral cameras for in vivo brain tissues and chromophore identification

doi: 10.1117/1.JBO.29.9.093510

Figure Lengend Snippet: Mean reflectance spectral signatures with a standard deviation of all pixels included inside the 5 × 5 ROIs from both HS cameras. The shorter spectral signatures from 661.61 to 951.42 nm with continuous lines correspond to the snapshot camera in panels (a) and (b), whereas the longer spectral signature with dashed lines corresponds to the linescan camera. On one hand, plots in panels (c) and (d) are the same as panels (a) and (b), but with emphasis on the area common to both. On the other hand, panels (e) and (f) are the normalized spectra from panels (c) and (d). The dashed rectangles indicate the spectral bands of the HS snapshot camera influenced by the infrared of the depth camera. (a) Calibrated and denoised healthy tissue. (b) Calibrated and denoised pathological tissue. (c) Calibrated and denoised healthy tissue after band removal. (d) Calibrated and denoised pathological tissue after band removal. (e) Calibrated, denoised, and normalized healthy tissue after band removal. (f) Calibrated, denoised, and normalized pathological tissue after band removal.

Article Snippet: Equation (1) eliminates the effect of the HS sensor and the lighting conditions captured with the raw images to obtain the reflectance information R from the sample, R = I raw − I dark I white − I dark , (1) where I raw is the captured raw data of the sample, I dark is the raw dark reference captured with the lens cap in front of the camera lens, and I white is the raw white reference intensity reflected over a Lambertian diffuse target with 95% of reflectance values (SG 3151-U, SphereOptics GmbH, Herrsching am Ammersee, Germany).

Techniques: Standard Deviation