Optical sensor having external cavity laser outputting sensing and reference light
AssigneeElectronics and Telecommunications Research Institute
InventorKwang Ryong Oh
Life of this patent
Estimating the term…
Abstract
Disclosed is an optical sensor, including an external cavity laser configured to output sensing light and reference light; and a photodetector configured to detect a beating signal by an interference of the sensing light and the reference light output from the external cavity laser, in which the external cavity laser includes a reflecting filter including a sensing grating, to which a sensing object is attachable, and a reference grating, which is disposed on the same plane as that of the sensing grating, and outputs sensing light reflected from the sensing grating and reference light reflected from the reference grating. Accordingly, the optical sensor does not require a high-resolution spectroscope and has improved resolution and sensitivity.
Claims19
An optical sensor, comprising:
- an external cavity laser configured to output sensing light and reference light;
- and
- a photodetector configured to detect a beating signal by an interference of the sensing light and the reference light output from the external cavity laser,
- wherein the external cavity laser includes a reflecting filter including a sensing grating, to which a sensing object is attachable, and a reference grating, which is disposed on the same plane as that of the sensing grating, and outputs sensing light reflected from the sensing grating and reference light reflected from the reference grating, and
- an oscillating part, in which a first channel light source outputting the reference light and a second channel light source outputting the sensing light are formed,
- wherein the oscillating part is located between the photodetector and the reflecting filter.
An optical sensor, comprising:
- an external cavity laser configured to output sensing light and reference light;
- a photodetector configured to detect a beating signal by an interference of the sensing light and the reference light output from the external cavity laser;
- and
- a coupler configured to optically couple the external cavity laser and the photodetector,
- wherein the external cavity laser includes
- a reflecting filter including a sensing grating, to which a sensing object is attachable, and a reference grating, which is disposed on the same plane as that of the sensing grating, and outputs sensing light reflected from the sensing grating and reference light reflected from the reference grating, and
- an oscillating part, in which a first channel light source outputting the reference light and a second channel light source outputting the sensing light are formed,
- wherein the oscillating part is located between the photodetector and the reflecting filter.
Dependencies are inferred from the claim text.