Dual confocal aperturing

Figure 1.7 Dual confocal aperturing achieved with a single physical aperture. Reproduced from Infrared Fourier Transform Spectrometry by P. R. Griffiths and ). A. de Haseth 2007, p. 307.

Figure 7.5 Radial integration of the optical sensitivity for a model Schwarschild objective when used in a standard (single-aperture) configuration (solid curve for the encircle intensity) and for the dual-aperture confocal configuration (dashed curve). A wavelength of 6 pm and Schwarschild optic having NA = 0.65 were assumed.

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