# finesse.detectors.compute.camera¶

Functions for computing images of a beam at arbitrary points in the interferometer configuration.

## Camera Equations¶

Each function in this sub-module has two modes - single frequency (mimicking amplitude detectors at each coordinate) and multi frequency (mimicking CCD cameras).

Single-frequency mode

If the argument f (i.e. the field frequency to probe) is specified then this function computes the amplitude and phase of the light field at this given frequency, for the specified x and y coordinate. The light field at frequency $$\omega_{\mathrm{i}}$$ is given by a complex number ($$z$$) and is calculated as follows:

$z(x, y) = \displaystyle\sum_{\mathrm{j}} \sum_{nm} u_{nm}(x, y) a_{\mathrm{j}nm} \quad\text{with}\quad \left\{\,\mathrm{j}\,|\,\mathrm{j} \in [0, \dots, N] \wedge \omega_{\mathrm{j}} = \omega_{\mathrm{i}}\right\}.$

Multi-frequency mode

Otherwise, if f is not specified, then this function acts like a CCD camera for the given pixel. It plots the beam intensity as a function of the x and y coordinates given. The output is a real number computed as:

$s(x, y) = \displaystyle\sum_{\mathrm{ij}} \sum_{nm} u_{nm}(x, y) u_{nm}^*(x,y) a_{\mathrm{i}nm} a_{\mathrm{j}nm}^* \quad\text{with}\quad \left\{\,\mathrm{i,j}\,|\,\mathrm{i,j} \in [0, \dots, N] \wedge \omega_{\mathrm{i}} = \omega_{\mathrm{j}}\right\}.$

## Functions¶

 field_pixel_output(CameraWorkspace cws, double f) ccd_pixel_output(CameraWorkspace cws) field_line_output(CameraWorkspace cws, …) ccd_line_output(CameraWorkspace cws, double[) field_camera_output(CameraWorkspace cws, …) ccd_output(CameraWorkspace cws, double[, )