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This page calculates the power received by a pixel of a camera viewing a scene. It calculates also the signal to noise ratio (SNR) from the main noise sources and the total SNR.

The scene is illuminated by a lambertian source at infinity and is considered as a lambertian diffuser, thus scattering light isotropically. The light source is specified by its radiance (source_rad) and its angular diameter (source_size). The scene is illuminated with an average angle of incidence inc_angle and is caracterized by its albedo (albedo).

The scene, located at the distance z_scene from the camera, is conjugated with the camera sensor thanks to a lens with given aperture diameter (aper_diam), magnification (magnification) and transmission (transmission). The scene sample viewed by the pixel is defined by its coordinates x_scene and y_scene in the plane XY perpendicular to the lens axis.

The camera is defined by its parameters : pixel size (pSize ), quantum efficiency (Qe ), dark current (dark_current ), readout noise (readOut_N), full well capacity (Full_Well_Cap), maximum exposure time (max_exp_time ) and integration time (int_time ). The quantum efficiency is condidered at the wavelength lambda corresponding to the average wavelength of the spectrum received by the camera.

The results encompass the scene irradiance (scene_irrad) as well as its radiance (scene_rad), the power received by the pixel, the SNR considering only the photon noise (SNR_Phot), the SNR considering only the dark current (SNR_Phot), the SNR considering only the dark current (SNR_Dark ), the SNR considering only the read out noise (SNR_Read) and the total SNR (SNR_Tot).

The list of links to the "Handy Calculations" executed for solving this usercase is displayed at the bottom of the page.