Abstract: Single-shot, adaptive metrology of rotationally variant optical surfaces, such as toroids, off-axis conies and freeform surfaces. An adaptive interferometric null test uses a high definition liquid crystal phase-only spatial light modulator (SLM) as the reconfigurable null element, on which a simulated nulling phase function is encoded, based on the specifications of the surface under test to generate a null interferogram. The power component of the surface sag is nulled by system design, not the SLM, enabling the SLM to fully compensate the residual departure without the need to tilt the optic or use a custom Offner-null. By wrapping the phase function at multiples of 2*pi radian, the upper limit in sag of the optic under test is theoretically removed.

Abstract: An echelle spectrometer includes a slit opening for incoming light, a collimator which collimates a diverging beam of light generated through the slit, a reflective echelle grating which disperses the collimated light along a first dimension; a cross-disperser which disperses at least a portion of the collimated light in a second dimension orthogonal to the first dimension to create a two-dimensional spectral field-of-view; and an imaging system which images the two-dimensional spectral field-of-view onto a detector; wherein the imaging system comprises primary, secondary, and tertiary tilted mirrors, where each of the tilted mirrors comprises a freeform, rotationally non-symmetric surface shape.

Abstract: A cascaded interferometric system for Fourier domain optical coherence tomography (OCT) in which the output of one sub-system interferometer is directed through a second sub-system interferometer for performing the Fourier transform in hardware.

Abstract: An echelle spectrometer includes a slit opening for incoming light, a collimator which collimates a diverging beam of light generated through the slit, a reflective echelle grating which disperses the collimated light along a first dimension; a cross-disperser which disperses at least a portion of the collimated light in a second dimension orthogonal to the first dimension to create a two-dimensional spectral field-of-view; and an imaging system which images the two- dimensional spectral field-of-view onto a detector; wherein the imaging system comprises primary, secondary, and tertiary tilted mirrors, where each of the tilted mirrors comprises a freeform, rotationally non-symmetric surface shape.

Abstract: Single-shot, adaptive metrology of rotationally variant optical surfaces, such as toroids, off-axis conies and freeform surfaces. An adaptive interferometric null test uses a high definition liquid crystal phase-only spatial light modulator (SLM) as the reconfigurable null element, on which a simulated nulling phase function is encoded, based on the specifications of the surface under test to generate a null interferogram. The power component of the surface sag is nulled by system design, not the SLM, enabling the SLM to fully compensate the residual departure without the need to tilt the optic or use a custom Offner-null. By wrapping the phase function at multiples of 2*pi radian, the upper limit in sag of the optic under test is theoretically removed.

Abstract: A cascaded interferometric system for Fourier domain optical coherence tomography (OCT) in which the output of one sub-system interferometer is directed through a second sub-system interferometer for performing the Fourier transform in hardware.