Systems and methods are disclosed for performing ophthalmic optical coherence tomography with multiple resolutions. In some embodiments, a system comprises a light source, an output lens, and a set of optical components between the light source and the output lens, the set of optical components comprising an afocal zoom telescope. The set of optical components is adapted to provide imaging both at a first field of view with a first resolution and at a second field of view with a second resolution, wherein the first field of view is wider than the second field of view and the second resolution is higher than the first resolution. A method of performing ophthalmic optical coherence tomography with multiple resolutions may be performed using one or more of the systems described herein.

A method for measuring interfaces of an optical element, forming part of a plurality of similar elements including at least one reference optical element, the method implemented by a device, the method including: relative positioning of each reference optical element and the measurement beam, to allow a measurement of interfaces of each reference optical element; acquisition of a reference image, of each reference element; positioning of the measured optical element to allow acquisition of a measurement image, of the optical element to be measured; determining a difference of position in a field of view of the measured element with respect to each reference optical element, based on the reference and measurement images; adjusting the position of the measured optical element in the field of view to cancel the difference of position; and measuring the interfaces of the measured optical element by the measurement beam.

An optical coherence tomography apparatus includes a control unit configured, before a tomographic image to be stored is obtained using the output from the light receiving unit during a period in which the measurement light is scanned in a first scanning pattern for scanning an image capturing region of the subject eye, to control the optical scanning unit so as to repeatedly scan the measurement light in a second scanning pattern for scanning the measurement light over at least part of the image capturing region in a scanning time shorter than a scanning time of the first scanning pattern and to control the driving unit so as to drive the focusing unit using the output from the light receiving unit during a period in which the measurement light is repeatedly scanned in the second scanning pattern.

Retinal imaging systems and related methods employ a user specific approach for controlling the reference arm length in an optical coherence tomography (OCT) imaging device. A method includes restraining a user's head relative to an OCT imaging device. A reference arm length adjustment module is controlled to vary a reference arm length to search a user specific range of reference arm lengths to identify a reference arm length for which the OCT image detector produces an OCT signal corresponding to the retina of the user. The user specific range of reference arm lengths covers a smaller range of reference arm lengths than a reference arm length adjustment range of the reference arm length adjustment module.

A heterogeneous integration detecting method and a heterogeneous integration detecting apparatus are provided. The heterogeneous integration detecting method includes the following. Under the condition of maintaining the same relative distance between an interference objective lens and a sample, the relative posture of the interference objective lens and the sample is continuously adjusted according to the change of an image of the sample in the field of view of the interference objective lens until a first optical axis of the interference objective lens is determined to be substantially perpendicular to the surface of the sample according to the image. The interference objective lens is replaced with an imaging objective lens and the geometric profile of at least one via of the sample is detected. A second optical axis of the imaging objective lens after replacement overlaps with the first optical axis of the interference objective lens before replacement.

An interference observation apparatus includes a light source, a splitting beam splitter, a combining beam splitter, a beam splitter, a mirror, a beam splitter, a mirror, a piezo element, a stage, an imaging unit, an image acquisition unit, and a control unit. An interference optical system from the splitting beam splitter to the combining beam splitter forms a Mach-Zehnder interferometer. The mirror freely moves in a direction perpendicular to a reflecting surface of the mirror. The total number of times of respective reflections of first split light and second split light in the interference optical system is an even number.

A optical measurement apparatus includes: an optical system which generates a pupil image of a measurement target, using light; a polarization generator which generates a polarized light from the light; a self-interference generator which generates a plurality of beams divided from the pupil image, using the polarized light, and causes the plurality of beams to interfere with each other to generate a self-interference image; and an image analysis unit configured to extract phase data from the self-interference image, and to move the measurement target to a focus position on the basis of the phase data.

Disclosed are several technical approaches of using low coherence interferometry techniques to create an autofocus apparatus for optical microscopy. These approaches allow automatic focusing on thin structures that are positioned closely to reflective surfaces and behind refractive material like a cover slip, and automated adjustment of focus position into the sample region without disturbance from reflection off adjacent surfaces. The measurement offset induced by refraction of material that covers the sample is compensated for. Proposed are techniques of an instrument that allows the automatic interchange of imaging objectives in a low coherence interferometry autofocus system, which is of major interest in combination with TDI (time delay integration) imaging, confocal and two-photon fluorescence microscopy.

Systems, devices and methods for measuring surface roughness and surface shape of an optical element using a dual-mode interferometer are disclosed. The devices implement optical filters, with a compact form, that allows measurement of both surface characteristics without rearranging the system components. One example interferometric system includes a laser light source and a low coherence light source that alternatively provide light to a collimator, followed by a polarizer, and a polarizing beam splitter. The system further includes two optical filters, a quarter waveplate, two objectives and a reference optical component. Each light source produces a set of interferograms, where one set of interferograms is used to measure the surface shape and another set of interferograms is used to measure the surface roughness of the optical component.

A device or apparatus is provided for carrying out measurements of shape on a first surface of a wafer relative to structures present beneath the first surface including (i) profilometry apparatus arranged in order to carry out measurements of shape on the first surface of the wafer according to at least one measurement field; (ii) imaging apparatus facing the profilometry apparatus and arranged in order to acquire a reference image of the structures on or through a second surface of the wafer opposite to the first surface according to at least one imaging field; the profilometry apparatus and said imaging apparatus being arranged so that the measurement and imaging fields are referenced in position within a common frame of reference.

A method is also provided to be implemented in this device or this apparatus.