Optical transmission device, laser module, failure detection method for laser module, and failure detection program for laser module

1. An optical transmission device capable of being coupled to an optical fiber, comprising:

a light source configured to emit a first light toward the optical fiber;

a lens configured to converge the first light to an end of the optical fiber;

a light reflector configured to reflect a first reflected light as a second reflected light, a part of the first light being reflected as the first reflected light by the lens or the optical fiber;

a first light receiver configured to receive the second reflected light; and

a detector configured to detect a failure based on a difference value between a first value corresponding to an amount of the second reflected light and a reference value being indicative of an amount of the second reflected light, the second reflected light being detected when the first light is normally emitted and is normally transmitted to and through the optical fiber.

2. The optical transmission device according to claim 1 , wherein the lens is coated an antireflective film on a surface thereof to reflect the first light of intensity in a predetermined range.

3. The optical transmission device according to claim 1 , wherein the light reflector reflects the first reflected light including a light from the end of the optical fiber, the end being polished at an angle so that the first light is reflected at the end.

4. The optical transmission device according to claim 1 , further comprising:

a storage configured to store reference value data corresponding to the reference value, wherein the detector detects the failure based on a difference between the first value and the reference value corresponding to the reference value data.

5. The optical transmission device according to claim 4 , further comprising:

an updater configured to acquire the reference value currently determined when the optical transmission device is started up and to update the reference value data with current reference value data corresponding to the reference value currently determined,

wherein the detector detects the failure based on the difference between the first value and the current reference value data.

6. The optical transmission device according to claim 5 , wherein

the updater acquires the reference value currently determined when the light emitted from the light source is varied and updates the reference value data with the current data corresponding to the reference value currently determined,

and the detector detects the failure based on the difference between the first value and the current reference value data.

7. The optical transmission device according to claim 5 , further comprising:

a second light receiver configured to receive a second light emitted from the light source and to output a second value corresponding to the received second light, the second light being emitted in a direction different from a direction toward the optical fiber,

wherein the updater acquires the reference value currently determined when the second value is varied and updates the reference value data with current data corresponding to the reference value currently determined,

and the detector detects a failure based on a difference between the first value and the current reference value data.

8. The optical transmission device according to claim 1 , wherein

the detector determines a disconnection of the optical fiber when the first value is larger than a first higher limit value defined as a sum of the first reference value and a first threshold, and determines an occurrence of a malfunction in an optical output unit when the first value is smaller than a first lower limit value defined as a sum of the reference value and a second threshold, the optical output unit including the light source, the optical fiber, and elements arranged therebetween associated with an propagation of the first light.

9. The optical transmission device according to claim 1 ,

wherein the detector determines a potential disconnection of the optical fiber when the first value is between a first higher limit value and a second higher limit value, the first higher limit value is defined as a sum of the first reference value and a first threshold and the second higher limit value is defined as a sum of the first reference value and a second threshold, and the first higher limit value is lager than the second higher limit value,

wherein the detector determines a disconnection of the optical fiber when the first value is lager than the first higher limit value,

wherein the detector determines a potential occurrence of a malfunction in an optical output unit when the first value is between a first lower limit value and a second lower limit value, the first lower limit value is defined as a sum of the first reference value and a third threshold and the second lower limit value is defined as a sum of the first reference value and a fourth threshold, and the first lower limit value is smaller than the second lower limit value, the optical output unit includes the light source, the optical fiber, and elements arranged therebetween associated with an propagation of the first light, and

wherein the detector determines a occurrence of the malfunction in the optical output unit when the first value is smaller than the first lower limit value.

10. A laser module capable of being optically coupled to an optical fiber, comprising:

a light source configured to emit a first light toward the optical fiber;

a lens configured to converge the first light to an end of the optical fiber;

a light reflector configured to reflect a first reflected light as a second reflected light, the first light being reflected as the first reflected light by the lens or the optical fiber;

a first light receiver configured to receive the second reflected light; and

a detector configured to detect a failure based on a difference value between a first value corresponding to an amount of the second reflected light and a reference value being indicative of an amount of the second reflected light, the second reflected light being detected when the first light is normally emitted and is normally transmitted to and through the optical fiber.

11. The laser module according to claim 10 , wherein the lens is coated an antireflective film on a surface thereof to reflect the first light of an intensity in a predetermined range.

12. The laser module according to claim 10 , wherein the light reflector reflects the first reflected light including a light from the end of the optical fiber, the end being polished at an angle so that the first light is reflected at the end.

13. A method for detecting a failure in a laser module capable of being optically coupled to an optical fiber, comprising:

emitting a first light, by the laser module, toward the optical fiber;

converging the first light to an end of the optical fiber;

reflecting a first reflected light to a second reflected light, the first light being reflected as the first reflected light by the optical fiber or when the first light propagates in the laser module;

receiving the second reflected light; and

detecting a failure based on a difference value between a first value corresponding to an amount of the second reflected light and a reference value being indicative of an amount of the second reflected light when the first light is normally generated and is normally transmitted to and through the optical fiber.

14. The method according to claim 13 , wherein

a lens included in the laser module is arranged on a path along which the first light propagates and the lens includes an antireflective film on a surface thereof to reflect the first light of intensity in a predetermined range.

15. The method according claim 13 , wherein

the first reflected light includes a light from the end of the optical fiber, the end being polished at an angle so that the first light is reflected at the end.

16. The optical transmission device according to claim 1 , further comprising:

a second light receiver configured to receive light third light from a light source in a direction away from the optical fiber; and

a second detector to detect the third light to monitor the light source.