A polarization holographic microscope system is disclosed. The polarization holographic microscope system can acquire a birefringence image and a three-dimensional phase image with high sensitivity by aperture synthesis of sample beams at various angles, and a sample image acquisition method using the microscope system.

A laser interference device includes a measurement laser that outputs a laser beam, a beam splitter that divides the laser beam into a measurement laser beam and a frequency monitor laser beam, a reference laser that outputs a reference laser beam, a frequency detector that detects a beat frequency resulting from interference between the reference laser beam and the frequency monitor laser beam, a wavelength calculator that calculates a wavelength of the frequency monitor laser beam (a wavelength measurement value) on the basis of the beat frequency, a light detector that detects an interference light of the measurement light and the reference light of the measurement laser beam and outputs a light detection signal, and a displacement calculator that calculates a displacement of the measurement mirror by performing an arithmetic process based on the wavelength measurement value and the light detection signal.

A pixelated color mask is combined with a pixelated polarization mask in dynamic interferometry. The color mask includes a wavelength-selective bandpass filter placed in front of each camera pixel such that each set of contiguous four camera pixels is covered by two green bandpass filters, a red bandpass filter, and a blue bandpass filter. The pixelated phase mask is coupled to the color filters such that one polarization filter covers one set of color filters. At least three polarization filters are used to calculate phase. In addition, the color signals can be used, for example, to encode the motion of the interferometer, to provide very high speed autofocus or tip/tilt feedback, to create a color image of the object being measured, to automatically focus the system at different positions for different measurements conducted with different color sources, and to perform heterodyne interferometry with a single, vibration-immune measurement.

An optical fiber splitter device comprising at least two optical fibers of different lengths is disclosed for partial or complete compensation of the optical path difference between waves interfering to generate a hologram or an interferogram. Various implementations of this fiber splitter device are described in apparatuses for holographic and interferometric imaging of microscopic and larger samples.

An interferometer includes a coherent light source and an array of electrically coupled light-sensitive pixel elements. The interferometer is configured to direct an internal optical path of the coherent light source and an external optical path of the coherent light source into a monolithic unit cell. In addition, the monolithic unit cell is configured to direct the internal optical path first through the monolithic unit cell and then onto the array and also configured to direct the external optical path back outside the monolithic unit cell through an external environment and then back into the monolithic unit cell and finally onto the array. In addition, interferometer is further configured to combine the internal optical path and the external optical path at the array and produce a first interferogram on the array, the interferogram characterizing an optical property of the external environment.

Reference and test waves are directed in a common path mode in a fiber tip diffraction interferometer. A first fiber can be used to generate the reference wave and a second fiber can be used to generate the test wave. Each fiber can include a single mode fiber tip that defines a wedge at an end without a coating on end surface or a tapered fiber tip. The fiber tip diffraction interferometer can include an aplanatic pupil imaging lens or system disposed to receive both the test wave and the reference wave and a sensor configured to receive both the test wave and the reference wave.

A laser interferometer includes a light source that emits first laser light, an optical modulator that includes a vibrator and modulates the first laser light by using the vibrator to generate second laser light including a modulated signal, a photodetector that receives interference light between third laser light including a sample signal generated by reflecting the first laser light on an object and the second laser light to output a light reception signal, a demodulation circuit that demodulates the sample signal from the light reception signal based on a reference signal, and an oscillation circuit that outputs the reference signal to the demodulation circuit, and the vibrator is a signal source of the oscillation circuit.

A method and a device for characterizing the surface shape of an optical element. In the method, in at least one interferogram measurement carried out by an interferometric test arrangement, a test wave reflected at the optical element is caused to be superimposed with a reference wave not reflected at the optical element. In this case, the figure of the optical element is determined on the basis of at least two interferogram measurements using electromagnetic radiation having in each case linear input polarization or in each case circular input polarization, wherein the input polarizations for the two interferogram measurements differ from one another.

Disclosed herein are optical integration technologies, designs, systems and methods directed toward Optical Coherence Tomography (OCT) and other interferometric optical sensor, ranging, and imaging systems wherein such systems, methods and structures employ tunable optical sources, coherent detection and other structures on a single or multichip monolithic integration. In contrast to contemporary, prior-art OCT systems and structures that employ simple, miniature optical bench technology using small optical components positioned on a substrate, systems and methods according to the present disclosure employ one or more photonic integrated circuits (PICs), use swept-source techniques, and employ a widely tunable optical source(s).

In another embodiment the system uses an optical photonic phased array. The phase array can be a static phased array to eliminate or augment the lens that couples light to and from a sample of interest or can be static and use a spectrally dispersive antenna and a tunable source to perform angular sweeping. The phased array can be active in 1 or 2 dimensions so as to scan the light beam in angle. The phased array can also adjust focus. The phased array can implement an optical waveform that will extend depth of field focus for imaging. The phase array can also be a separate standalone element that is fed by one or more optical fibers. The phased array can be for scanning a biomedical specimen used in conjunction with a swept-source OCT system, can be used in a free-space coherent optical communication system for beam pointing or tracking, used in LIDAR applications, or many other beam control or beam steering applications.

Method and system for determining separation distance between an object and a processing or measuring tool involve generating a measurement beam of low coherence optical radiation, leading the measurement beam towards the object and the reflected measurement beam towards an optical interferometric sensor assembly in a first direction of incidence, generating a reference beam of low coherence optical radiation, and leading the reference beam towards the optical interferometric sensor assembly in a second direction of incidence, superimposing the measurement and reference beams on a common region of incidence, detecting position of a pattern of interference fringes between the measurement and reference beams on the region of incidence, and determining difference in optical length between a measurement optical path and a reference optical path on position of the pattern of interference fringes along an illumination axis to determine current separation distance between the processing or measuring tool and the object.