| 摘要 |
A pyroelectric element 10 includes a pyroelectric substrate 20 being a substrate of lithium tantalate single crystal having an X-axis, a Y-axis, and a Z-axis as crystal axes; front-side electrodes 41 and 42 disposed on a front side of the pyroelectric substrate 20; and back-side electrodes 51 and 52 paired with the front-side electrodes 41 and 42, respectively. The pyroelectric substrate 20 is a Y-offcut plate obtained by cutting the lithium tantalate single crystal at an angle turned by a cut angle ¸ from the Y-axis toward the Z-axis about the X-axis that coincides with a direction along the electrode plane, and the cut angle ¸ is 30° to 60° or 120° to 150°. The pyroelectric substrate 20 is preferably 10 µ m or less in thickness, and is more preferably 5 µ m to 10 µ m in thickness. |
