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Based on the principle of non-imaging optics, the illumination system with the laser diode (LD) array is designed for new laser projection system in this paper. Both illumination system designs of the light pipe and fly's eye lens array are presented using standard optical design software Zemax, including the shaping design of laser source beam, uniform light system design and the relay lens design. Good performances are achieved in the simulation. Energy efficiencies of two designs are 65% and both of beam uniformities are near to 96% in the illumination system.

In this paper we repot the field demonstration of fiber laser seismic system. The structure of the fiber laser geophone, the seismic towed array, the interrogator system, and the test results are given. The results show that the four-element fiber laser seismic array have good performance.

We present a method of target detection against strong light based on gate viewing. In this method, a nanosecond-scale gate shutter is used to control the exposure time of CCD and reduce the collection of obtrusive light, and a nanosecond-scale pulsed laser is used to illuminate targets and increase signal energy. By matching them, the ratio between signal and obtrusive light will be significantly improved to detect targets against light disturbance. We have analyzed the method in theory, and performed it in experiment. In addition, a stroboscopic time sequence is used, and the setting of temporal parameters is also discussed.

How to simulate the decay pattern is crucial during lifetime inversion while utilizing intensity images acquired at increasing delays in time gated fluorescence lifetime imaging microscopy (FLIM) method. A relatively novel understanding of fluorescence decay pattern theory and stimulation algorithms of time gated FLIM method have been analyzed in this paper comprehensively. Main lifetime computing algorithms can be classified as exponential pattern retrieve and polynomial fitting procedure. Especially, a novel lifetime computing method based on bi-exponential decay has been discussed. In experiment, we have validated the proposed algorithms utilizing synthetic images. Performances like calculating precision and computing speed of the algorithms above have also been compared.

This paper presents a novel algorithm to extract signal area of range-gated images under the EBE effect. Besides the histogram information, this algorithm uses average gray value information to select threshold with iterative processing. With average gray value information, the edges of signal area can be segmented out accurately. The algorithm can handle images under the impact of EBE effect, reduce the noise in the images and segment the objects from the noise area effectively without many morphological operations which keeps the certain figure from distortion. Experiment result shows that the algorithm is effective to the signal areas extraction of images under EBE effect, signal areas can be segmented out accurately.

A novel fiber laser vector hydrophone (FLVH) based on accelerometers is presented. Three fiber laser accelerometers (FLA), perpendicular to each other, are used to detect the acoustic induced particle acceleration. Theoretical analyses of the acoustic sensitivity and the natural frequency are given. Experiment shows a sensitivity of 0.1 pm/Pa@100 Hz is achieved, which results in a minimum detectable acoustic signal of 100 Pa/@Hz@100 Hz. Field demonstration shows that the proposed vector hydrophone has good directivity.

A fiber laser hydrophone (FLH) based on a flat diaphragm and an L shaped lever is presented. This hydrophone uses an L shaped lever to transfer the acoustic pressure induced defection of the flat diaphragm to the axial elongation of the fiber laser. The curve where the L shaped lever contacts the diaphragm is a segment of an Archimedes spiral, which is used to enhance the responsivity. To compensate the hydrostatic pressure, a capillary tube is fixed at the end of the hydrophone. Both theoretical and experimental investigations are presented in this paper. The result shows that the proposed design has a high sensitivity of a flat frequency response below 1 kHz.

In this paper, we design a high power and small volume laser source module using the laser diode array for the laser projector system. This module can efficiently suppress speckle noise by reducing the phase coherence using laser diode array. In addition, we use the rotating diffuser to further disturb the coherence of the lasers for lower speckle noise. The experimental results show that the laser source module and the rotating diffuser can effectively eliminate the speckle noise. This new light module with laser diode array can be used in the laser projection system with high brightness, small volume and low speckle noise.

In this paper, we design a high power and small volume laser projector using the red laser diode, green laser diode, blue laser diode and green fluorescence as light source, which could improve the performance of the projector significantly with longer lifetime than lamps, higher reliability, and larger color gamut. According to the requirement of CIE Standard Illuminant D65 and light output, the power of red laser diode, green laser diode, blue laser diode and green fluorescence were calculated. The energy efficiency of four base-color optical path was also analyzed. It could be concluded that the blue laser and red laser have higher power requirements.

We propose a surveillance photonic fence for night remote intrusion detection, especially in bad environmental conditions. The photonic fence is established by the synchronization of a pulsed infrared laser and a gated imaging sensor. Since the wavelength of the laser is invisible, the photonic fence is also invisible. Only when targets pass the fence, their image information can be collected. Objects and backgrounds out of the fence are all filtered directly which decreases the complexity of image processing about target extraction. For the fence, its location can be easily adjusted by the delay time between the laser pulse and the gate pulse, and its thickness can be set by changing the gate time and the laser pulse width. Furthermore, target space information can also be estimated in terms of the range information of the photonic fence.

We demonstrate a high performance wavelength demodulator for DFB FL sensor using novel PGC algorithm and reference compensation method (RCM). An unbalanced fiber Michelson interferometer is employed and the phase demodulation is accomplished by a digital PGC-Arctan-DSM algorithm. The RCM is adopted to eliminate the environmental noise using a shielded and multiplexed DFB FL as a reference. Experimental results have demonstrated a resolution of 3.5×10-7 pm/√Hz, a dynamic range of 120 dB @ 100 Hz, a THD of below 0.1 %, and a linearity of 99.99 %. More than 50 dB reduction of the environmental noise has been experimentally achieved within 10-1000 Hz.