Abstract: This invention enables the full-body (throughout the entire thickness) scribing of a plate made of fragile material such as glass by irradiating the work with the laser beam for heating with or without cooling and thereby generating the tensile thermal stress in the work which exceeds the cleavage toughness of the material, dispensing with the mechanical breaking. In this invention, the absorption of the beam in the work is so controlled that the beam, while being absorbed in it, is either transmitted through it or reaches the adequate thickness of the work and the entire thickness scribing is realized. This absorption control is done by selecting the laser beam wavelength so as to achieve the proper absorption in the absorption spectra of the material either due to the electronic transition or the lattice vibration.