EMITTING OPTICAL PART AND DIFFRACTION GRATING DEVICE

摘要

PURPOSE: To provide an emitting optical part (diffraction grating device) by which the assembling steps can be reduced with a small number of parts therein. CONSTITUTION: The diffraction grating device is provided with a holder part 22 which houses and holds a light emitting element 10 on one end side thereof and a diffraction grating body 21 which diffracts a light emitted from the element 10 on the other end side thereof, and a holder 22 is integrally formed together with the body 21. The contact face between the element 10 and holder 22 and the outer side face of the holder 22 are coated with a substance 22a with a high thermal conductivity that is thermally in contact with the element 10. A cap 30 made of a material with a proper thermal radiating property is provided with a projection part 31 engaging with a recessed part of the part 22, and it is engaged with the holder 22 in a manner to cover the element 10 in such a state that it is thermally in contact with the element 10.