Various optical systems equipped with diode laser light sources are discussed in the present application. One example system includes a diode laser light source for providing, a beam of radiation. The diode laser has a spectral output bandwidth when driven under equilibrium conditions. The system further includes a driver circuit to apply a pulse of drive current to the diode laser. The pulse causes a variation in the output wavelength of the diode laser during the pulse such that the spectral output bandwidth is at least two times larger the spectral output bandwidth under the equilibrium conditions.

A grating measuring device includes: a light source module (300) for generating two light beams having different frequencies, one of which serves as a measuring beam and the other as a reference beam; a grating (200); and a grating measuring probe (100) including a dual-frequency light reception module, a vertical measurement module, a vertical detection module and a reference detection module. The dual-frequency light reception module is configured to receive the measuring and reference beams, and the vertical measurement module is adapted to project the measuring beam onto the grating (200), collect a zeroth-order diffracted beam resulting from double diffraction occurring at the grating, and feed the zeroth-order diffracted beam to the vertical detection module. The zeroth-order diffracted beam interferes with the reference beam in the vertical detection module, resulting in a vertical interference signal. In addition, the measuring and reference beams interfere with each other also in the reference detection module to result in a reference interference signal. The vertical and reference interference signals are received by a signal processing module and serve as a basis for calculating a vertical displacement of the grating (200). This grating measuring device allows a great vertical displacement measurement range at any working distance.

Disclosed is a three-dimensional shape measuring apparatus using a diffraction grating, comprising: a light splitter installed in a traveling direction of a light generated from a light source unit and configured to reflect a portion of the light along a first path and transmit a portion of the light along a second path; an image sensor unit configured to receive a light traveling along the first path and reflected from a measurement target having at least one hole, and measure the shape of the measurement target; and a diffraction grating disposed on at least one light path among a light path between the light source unit and the light splitter, a light path between the measurement target and the light splitter, and a light path between the measurement target and the image sensor unit.

The interferometer 10 according to this disclosure includes: a first optical component 12 that splits each of the P polarization component and the S polarization component of the light to be measured into the first optical path R1 and the second optical path R2 and combines the light to be measured; a second optical component 13 placed in the first optical path; a third optical component 14 that splits the light to be measured into the P polarization component and the S polarization component; and a P polarization detector 11a and an S polarization detector 11b that respectively detect the P polarization component and the S polarization component split by the third optical component, wherein the second optical component has an optical surface that changes the propagation direction of the light to be measured and gives a phase difference between the P polarization component and the S polarization component.

The invention relates to an apparatus of inner light layer illumination for optical imaging in turbid media. This apparatus comprises laser generating short light pulse(s), negative dispersion device to broaden the width of the short light pulse(s) before the pulse(s) enter(s) the turbid medium, imaging distance adjuster changing the imaging distance and optical receiver receiving returned signal light pulse(s). This apparatus can reduce absorption and scattering of the turbid media greatly and create an inner light layer with strong intensity to illuminate the object in the turbid medium. The mathematical calculations have proved that this apparatus can enhance the signal strength by more than 600 dB. The imaging depth can be over 5 cm in human body, and more than 500 m in clear seawater. The imaging resolutions are <1 micrometer along object plane and are approximate 1 micrometer along direction of depth of field.

A signal processing device includes a controller which acquires an output signal output from a single light receiver that receives a plurality of interference beams in which a light beam that is output from a single light source and traces a sample arm toward a measurement target and a light beam that is output from the light source and traces a reference arm that is different from the sample arm interfere with each other, the plurality of interference beams each having a different wavelength dispersion characteristic difference between the sample arm and the reference arm traced by the light beams interfering with each other; and extracts an extraction signal that is a signal for each of the interference beams on the basis of the output signal acquired and a correction signal obtained by applying wavelength dispersion correction processing to the output signal.

Various optical systems equipped with diode laser light sources are discussed in the present application. One example system includes a diode laser light source for providing a beam of radiation. The diode laser has a spectral output bandwidth when driven under equilibrium conditions. The system further includes a driver circuit to apply a pulse of drive current to the diode laser. The pulse causes a variation in the output wavelength of the diode laser during the pulse such that the spectral output bandwidth is at least two times larger the spectral output bandwidth under the equilibrium conditions.

A displacement detecting device includes a first diffraction grating, a light source, a displacement detecting unit, and a light receiving unit. The displacement detecting unit includes a light flux dividing unit, a second diffraction grating, and a reference reflecting member. An incident angle of a first light flux to the first diffraction grating, a diffraction angle of the first diffraction grating, an incident angle of the first light flux to the second diffraction grating, and a diffraction angle of the second diffraction grating are angles at which a displacement amount in an optical path length of the first light flux from the light flux dividing unit to the first diffraction grating and a displacement amount in an optical path length of the first light flux from the first diffraction grating to the second diffraction grating become equal in a case where a measured member is displaced in a direction orthogonal to a measured surface.

A grating measuring device includes: a light source module (300) for generating two light beams having different frequencies, one of which serves as a measuring beam and the other as a reference beam; a grating (200); and a grating measuring probe (100) including a dual-frequency light reception module, a vertical measurement module, a vertical detection module and a reference detection module. The dual-frequency light reception module is configured to receive the measuring and reference beams, and the vertical measurement module is adapted to project the measuring beam onto the grating (200), collect a zeroth-order diffracted beam resulting from double diffraction occurring at the grating, and feed the zeroth-order diffracted beam to the vertical detection module. The zeroth-order diffracted beam interferes with the reference beam in the vertical detection module, resulting in a vertical interference signal. In addition, the measuring and reference beams interfere with each other also in the reference detection module to result in a reference interference signal. The vertical and reference interference signals are received by a signal processing module and serve as a basis for calculating a vertical displacement of the grating (200). This grating measuring device allows a great vertical displacement measurement range at any working distance.

According to embodiments of the present invention, an optical imaging device is provided. The optical imaging device includes an optics arrangement configured to generate an extended-source illumination pattern including a plurality of separate spectral bands, and to illuminate a respective section of a sample to be imaged with a respective spectral band of the plurality of separate spectral bands, wherein the optics arrangement is further configured to form an interference signal from a sample light comprising respective return lights from respective sections of the sample illuminated by respective spectral bands of the extended-source illumination pattern, and a reference light, and a detector configured to receive the interference signal for generating an image corresponding to the sections of the sample. According to further embodiments of the present invention, a method for imaging a sample and a method for generating an image are also provided.