| 摘要 |
<p>PROBLEM TO BE SOLVED: To suppress changes in the wavelength reversal characteristics in a polarization reversal crystal due to temperature change. SOLUTION: A ferroelectric crystal 1 is provided with a periodical polarization reversal structure 2 and further provided with a charge neutralizing means to neutralize the excess and deficiency of charges appearing on the crystal surface in different regions on the crystal surface. The charge neutralizing means is represented mostly by two embodiments. In one embodiment as shown in Fig 1 (a), the periodical polarization reversal structure is formed in a part of the ferroelectric crystal and other region is formed as a multidomain structure. In the other embodiment, a conductive coating layer is formed on the surface of the ferroelectric crystal to eliminate the excess and deficiency of charges by short-circuiting.</p> |
