A computer-implemented method includes: receiving, by a computing device, data corresponding to a dynamic speckle spectrum image associated with a biological sample; comparing, by the computing device, the dynamic speckle spectrum image with a plurality of training images; classifying, by the computing device, a contaminant present in the biological sample, based on the comparing; and providing, by the computing device, information regarding the classification of the contaminant.

Disclosed herein are electronic devices having touch input surfaces. A user's touch input or press on the touch input surface is detected using a set of lasers, such as vertical-cavity surface-emitting lasers (VCSELs) that emit beams of light toward the touch input surface. The user's touch causes changes in the self-mixing interference within the VCSEL of the emitted light with reflected light, such as from the touch input surface. Deflection and movement (e.g., drag motion) of the user's touch is determined from detected changes in the VCSELs' operation due to the self-mixing interference.

A laser interferometer includes alight 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 for detecting a gaze direction of an eye includes the steps of irradiating at least one wavelength-modulated laser beam onto an eye, detecting an optical path length of the emitted laser beam based on laser feedback interferometry of the emitted laser radiation with a backscattered radiation from the eye, detecting a Doppler shift of the emitted radiation and the backscattered radiation based on the laser feedback interferometry, detecting an eye velocity based on the Doppler shift, and detecting an eye movement of the eye based on the optical path length and the eye velocity.

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 a signal generator that outputs the reference signal input to the demodulation circuit and outputs a drive signal input to the optical modulator, in which Vd/Vr<10, where Vr is a voltage of the reference signal and Vd is a voltage of the drive signal.

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, and an optical path length variable section that changes an optical path length of an optical path through which the third laser light propagates.

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.

Disclosed herein are electronic devices having touch input surfaces. A user's touch input or press on the touch input surface is detected using a set of lasers, such as vertical-cavity surface-emitting lasers (VCSELs) that emit beams of light toward the touch input surface. The user's touch causes changes in the self-mixing interference within the VCSEL of the emitted light with reflected light, such as from the touch input surface. Deflection and movement (e.g., drag motion) of the user's touch is determined from detected changes in the VCSELs' operation due to the self-mixing interference.

The invention is related to a laser diode based multiple beam laser spot imaging system for characterization of vehicle dynamics. A laser diode based, preferably VCSEL based laser imaging system is utilized to characterize the vehicle dynamics. One or more laser beams are directed to the road surface. A compact imaging system including an imaging matrix sensor such as a CCD or CMOS camera measures locations or separations of individual laser spots. Loading status of vehicles and vehicles' pitch and roll angle can be characterized by analyzing the change of laser spot locations or separations.

There is provided a scattered light signal measurement apparatus and an information processing apparatus that are capable of performing accurate measurement while preventing noise due to changes in relative velocity and relative position caused between a sensor and an observation target. The scattered light signal measurement apparatus includes a light receiving element and an incident angle limiting unit. The light receiving element receives scattered light obtained when coherent light emitted to a measurement target is scattered by the measurement target. The incident angle limiting unit limits an incident angle of the scattered light that is incident on a single point of the light receiving element to be equal to or smaller than a predetermined angle and controls the single light receiving element to increase an aperture ratio.