| 摘要 |
A grating device includes a support substrate, an optical material layer 11 disposed on the support substrate and having a thickness of 0.5 µm or more and 3.0 µm or less, a ridge optical waveguide formed by a pair of ridge grooves in the optical material layer and having a light-receiving surface for receiving a semiconductor laser light and a light-emitting surface for emitting light having a desired wavelength, a Bragg grating 12 comprising convexes and concaves formed in the ridge optical waveguide, and a propagating portion 13 disposed between the light-receiving surface and the Bragg grating. The relationships represented by the following Formulas (1) to (4) are satisfied: 0.8 nm ‰¤”»G‰¤ 6.0 nm ··· (1); 10 µm ‰¤Lb ‰¤ 300 µm ··· (2); 20 nm ‰¤ td ‰¤ 250 nm ··· (3); and nb ‰¥ 1.8 ··· (4). |
