Calibration And Characterization ================================ UUID: ``B8B41A65-2C29-4D60-A101-7072DA9F7646`` Calibration converts the raw CCD/ADC stream into a more useful spectrum. Characterization measures how well that calibrated result matches known optical inputs. The project uses CIE 233:2019 and ASTM E275 as technical references for array spectroradiometer calibration and UV-Vis spectrometer performance measurement. Calibration Pipeline -------------------- The host app's processing order is: 1. Convert raw ADC counts to floating-point values. 2. Remove stored master bias ``B_p`` when configured. 3. Estimate a frame-wise dark reference from shielded pixels 16 through 28 when dark subtraction is enabled. 4. Convert the inverted CCD readout into light-tracking counts. 5. Apply stored master-dark offsets if configured. 6. Apply flat-field or PRNU multiplicative correction when enabled. 7. Apply wavelength-dependent QE/response correction when enabled. 8. Build wavelengths from stored polynomial coefficients. 9. Normalize the display by absolute saturation reference or per-frame peak. Characterization Tests ---------------------- The characterization plan should record: * Wavelength-map fit residuals using laser diodes or known emission lines. * FWHM of narrow lines at multiple wavelengths. * SNR versus wavelength, especially near 850-1000 nm where detector response is expected to be lower. * Linearity versus input level and integration time. * Repeatability over repeated acquisitions without realignment. * Stray-light and second-order diffraction behavior with and without filtering. * Comparison against a reference source or commercial spectrometer. Calibration and characterization are coupled. Wavelength error depends on optical alignment, grating angle, CCD placement, and the pixel-to-wavelength curve. Intensity error depends on the CCD response, mirror and grating efficiency, filter transmission, analog acquisition chain, integration time, and the software correction factors. .. _uuid-c2aaf1f1-4b20-4d93-92c4-40b86483492c: Verification Methods And Evidence --------------------------------- UUID: :ref:`C2AAF1F1-4B20-4D93-92C4-40B86483492C ` Calibration and characterization results remain planned until their method, criterion, measurement conditions, uncertainty context, evidence artifacts, and review disposition are recorded. The requirements-linked methods and evidence-package rules are defined in :doc:`Test and Verification `.