讨论了利用布拉格衍射对水中目标进行声光成像的原理和方法。使用低频超声波对目标进行“照射”,反射回波经倍频处理使其频率提高到10~7-10~8Hz的数量级,以便既能缩小系统的尺寸又能实现布拉格衍射。分析与计算表明,布拉格成像系统能对20m以内的目标进行清晰的成像。这种方法用于对水中物体,特别是混浊水中物体进行实时探测和观察非常有效。 The principle and method of using acousto-optic imaging with Bragg diffraction to discuss underwater target are discussed. The target is “irradiated” with low-frequency ultrasound, and the frequency of the reflected echo is multiplied to increase the frequency to the order of 10-7-10-8Hz to reduce the size of the system and to achieve Bragg diffraction. Analysis and calculation show that Bragg imaging system can clearly image the target within 20m. This method is very effective for real-time detection and observation of objects in water, especially turbid water.