Water-jet guided laser cutting technology is a new type of cutting method using the water jet to guide the laser to the machining plane and have great advantages for its small heat affected zone, high precision and no pollution. In the review article, the domestic and international research progress of water-jet guided laser cutting is introduced in theory and processing. Besides, technical difficulties and development in this technique are discussed. Optical components are serviced as imaging element, such as a lens, a prism, a reflector, etc. In addition, some optical elements play a special role in the optical system, such as reticle plate, filter, grating. In this issue, several different optical components are introduced. Designing and data analyzing in interference or imaging systems are also demonstrated.