Crystal oscillators are loosely divided through the frequency they perform at and whether they are essential oscillators—operate with the frequency marked around the can or at even multiples of that (overtone oscillators). Superior-repetition-level and large-ability picosecond regenerative amplifier according to one bulk Nd:GdVO4 crystal 中原子或分子的排列具有三维空间的周期性，隔一定... https://yoursocialpeople.com/story4323997/a-review-of-bulk-crystal-oscillator