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We report the demonstration of passively continuous-wave mode-locking (CWML) of diode-pumped Tm,Ho:YVO4 laser using an InGaAs/GaAs multiple quantum-well (MQW) structure semiconductor as the saturable absorber. Stable mode-locking pulses at the central wavelength of 2 041 nm are obtained. The maximum output power is 151 mW. The pulse duration is 10.5 ps at the repetition rate of 64.3 MHz.

We report on a high energy, high repetition rate Ho:YAG master oscillator and power amplifier (MOPA), resonantly dual-end-pumped by Tm:YLF lasers at room temperature. At the pulse repetition frequency of 1 kHz, we demonstrate a maximum energy of 30 mJ per pulse with a 28.2 ns pulse width in a Ho:YAG oscillator system resonantly double-end-pumped by Tm:YLF lasers. A maximum energy of 52 mJ per pulse with a 30.5 ns pulse width is achieved in the Ho:YAG amplifier, corresponding to a peak power of approximately 1.7 MW. The output wavelength is at 2090.6 nm and 2096.9 nm, and a beam quality factor of 𝑀 2 ∼2.1 is achieved.

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The single-pixel imaging (SPI) technique is able to capture two-dimensional (2D) images without conventional array sensors by using a photodiode. As a novel scheme, Fourier single-pixel imaging (FSI) has been proven capable of reconstructing high-quality images. Due to the fact that the Fourier basis patterns (also known as grayscale sinusoidal patterns) cannot be well displayed on the digital micromirror device (DMD), a fast FSI system is proposed to solve this problem by binarizing Fourier pattern through a dithering algorithm. However, the traditional dithering algorithm leads to low quality as the extra noise is inevitably induced in the reconstructed images. In this paper, we report a better dithering algorithm to binarize Fourier pattern, which utilizes the Sierra–Lite kernel function by a serpentine scanning method. Numerical simulation and experiment demonstrate that the proposed algorithm is able to achieve higher quality under different sampling ratios.