Diffuse image measurement system and digital image formation method. The system includes a source of light with time-varying intensity directed at a scene to be imaged. A time-resolved light meter is provided for receiving light reflected from the scene to generate time-resolved samples of the intensity of light incident at the light meter. The temporal variation in the intensity of light incident at the light meter is associated with a function of a radiometric property of the scene, such as a linear functional of reflectance, and a computer processes the samples to construct a digital image. The spatial resolution of the digital image is finer than the spatial support of the illumination on the scene and finer than the spatial support of the sensitivity of the light meter. Using appropriate light sources instead of impulsive illumination significantly improves signal-to-noise ratio and reconstruction quality.

An imaging unit for an ultrafast imaging apparatus includes an objective lens opposing a workpiece supported on a chuck table, a beam splitter disposed in a first optical path extending from the objective lens, an image processing unit disposed in a second optical path extending from the beam splitter, and an illumination unit disposed in a third optical path extending from the beam splitter. The illumination unit includes a broadband pulsed light source, and a spectrometer configured to divide a single pulse of light, which has been emitted from the broadband pulsed light source, into a plurality of wavelengths and to produce a time lag between each two adjacent ones of the plurality of wavelengths.

An imaging unit for an ultrafast imaging apparatus includes an objective lens opposing a workpiece supported on a chuck table, a beam splitter disposed in a first optical path extending from the objective lens, an image processing unit disposed in a second optical path extending from the beam splitter, and an illumination unit disposed in a third optical path extending from the beam splitter. The illumination unit includes a broadband pulsed light source, and a spectrometer configured to divide a single pulse of light, which has been emitted from the broadband pulsed light source, into a plurality of wavelengths and to produce a time lag between each two adjacent ones of the plurality of wavelengths.

The present disclosure claims an apparatus, a method and a system for the calibration of a streak camera. A plurality of fiber optic cables is bundled together such that the input ends and the output ends of the fibers are grouped together. Each fiber in the bundle has a distinct and characteristic time taken for light to traverse from the input end to the output end known by the observer. This characteristic time depends on the physical and optical properties of the fibers selected. Calibration light is collected by the fiber input face and travels through the individual fibers in a characteristic time. Individual light pulses will subsequently be detected by the streak camera which converts the time profile of the incoming light pulses into a spatial profile. An observer can compare the observed spatial separation profile to an expected spatial separation profile for calibration.

The present application relates to the technical field of ultrafast imaging, and provides an ultrafast framing optical imaging device with a real-time high spatial resolution. The optical imaging device includes an ultrashort pulse laser system with a magnitude of femtosecond, a frequency multiplier, a wavelength splitter, a continuous illumination laser, a sampling plate, a calibration camera, a first imaging record module, and a second imaging record module. The present application mainly utilizes continuous light illumination ultrafast events and non-collinear light parameter amplifying technology that uses ultrashort pulse laser to pump/sample events at different moments, and adopts a plurality of CCD cameras to receive corresponding idle light images simultaneously and respectively and thereby realize ultrafast framing optical imaging with a high time resolution.