Gas detecting device including light emitter, light receiver, and an optical member
A device includes a light emitting element, a light receiving element, an electronic part capable of processing a signal output from the light receiving element, an optical member covering the light emitting element and the light receiving element, and a board on which the light emitting element, the light receiving element, the electronic part, and the optical member are mounted. The board includes conductor wiring electrically connected to the light receiving element.
1. A device comprising:
a light emitting element;
a light receiving element;
an electronic part for processing a signal output from the light receiving element;
an optical member covering the light emitting element and the light receiving element; and
a board having a main surface on which the electronic part is disposed; and
a support body disposed on the main surface of the board and surrounding the electronic part,
wherein the light emitting element and the light receiving element are disposed on the support body along a normal direction of the main surface of the board, the normal direction being perpendicular to the main surface of the board, such that the support body is disposed between the board and both the light emitting element and light receiving element, and
the board includes a terminal electrically connected to the light receiving element, the terminal is disposed on the main surface outside the support body and is not covered by the support body, while the electronic part are disposed on the main surface inside the support body, when the device is viewed from the normal direction of the main surface.
2. The device according to claim 1 , further comprising a reflection body disposed above the light emitting element and the light receiving element, and provided with a first opening immediately above the light emitting element and a second opening immediately above the light receiving element.
3. The device according to claim 2 , wherein the support body further comprises an accommodation recess, and the reflection body is disposed in the accommodation recess.
4. The device according to claim 1 , wherein the support body includes a recess having stepped side surfaces, and the device further comprises an optical filter disposed on the stepped side surfaces of the recess and laid on an optical path for guiding infrared light from the light emitting element toward the light receiving element side, and for transmitting infrared light in a predetermined wavelength band.
5. The device according to claim 4 , wherein
the optical filter includes a first optical filter having a transmission band containing a wavelength band of infrared light absorbed by gas that is a detection target, and a second optical filter having a transmission band different from the transmission band of the first optical filter, and
the light receiving element includes a first light receiving element for photoelectrically converting infrared light transmitted through the first optical filter, and a second light receiving element for photoelectrically converting infrared light transmitted through the second optical filter.
6. The device according to claim 1 , wherein the optical member has a larger length in a vertical direction than in a planar direction.
7. The device according to claim 4 , wherein the stepped side surfaces have a depth in a direction of a thickness of the support body equal to the thickness of each of the optical filters.