KR20030089633A - Optical transceiver - Google Patents

Abstract

The present invention provides an optical transmission and reception device which can reduce the number of optical elements as much as possible and at the same time use many common parts in the first and second optical modules, thereby reducing the manufacturing cost.

The first and second optical modules 30 and 60 may include light emitting devices 52 and 82 that emit light of the first or second wavelengths λ 1 and λ 2, and light receiving elements 53 that receive light from the optical fiber 12. 83, optical members 40 and 70 for condensing light from the light emitting element to the optical fiber and condensing light from the optical fiber, and directing light from the light emitting element to the optical fiber side to diffract light from the optical fiber Is a light transmitting / receiving device having first and second diffraction gratings 42 and 72 for emitting to the light receiving element side, the pitch of the first diffraction grating is formed as P1, and the pitch P2 of the second diffraction grating is formed. It formed as P1x ((lambda) 1 / (lambda) 2).

Description

Optical transmitting and receiving device {OPTICAL TRANSCEIVER}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical transmission and reception device, and more particularly, to an optical transmission and reception device which can be manufactured at low cost by promoting the use of parts and assembly jigs.

The optical module 20 has a configuration as shown in FIG. 3 in connecting the two optical modules 20 installed in the terminal of the optical communication with the optical fiber 12 to receive a large amount of data at high speed over a long distance. . In this example, each optical module 20 enters the optical fiber 12 with light having a first wavelength (λ = 1310 nm from one side and λ = 1550 nm from the other) emitted from the laser diode 11 as a light emitting element. At the same time, light of another wavelength emitted from the optical fiber 12 (lambda = 1550 nm from one side and lambda = 1310 nm from the other side) is received by the photodiode 13 serving as a light receiving element.

In addition, the optical transmitting and receiving device is provided in close proximity to the first collimation lens 21 provided in close proximity to the laser diode 11, the second collimation lens 22 provided in proximity to the optical fiber 12 and the photodiode 13. A third collimation lens 23 is provided, and an optical filter 24 is disposed between the first and second collimation lenses 21 and 22 so as to be inclined at 45 degrees with respect to the optical axis.

According to this optical transmitting and receiving device, the light of the first wavelength λ1 emitted from the light emitting element 15 of the laser diode 11 becomes parallel light by the first collimation lens 21, and the optical filter 24 After passing through the light, the light is collected by the second collimation lens 22 and incident on the optical fiber 12.

The light of the second wavelength λ2 emitted from the optical fiber 12 becomes parallel light by the second collimation lens 22, is reflected by the optical filter 24, and the third collimation lens 23. Is focused on the light receiving element 14 of the photodiode 13.

By the way, the optical filter comprised by laminating | stacking three collimation lenses and a multilayer film is used for the said conventional optical transmitting / receiving apparatus, and there are many parts. Moreover, each component is dedicated to the wavelength of the light which receives light, and each arrangement position must be changed, and the kind of components increases. As a result, assembly adjustment takes time and costs are high.

Accordingly, an object of the present invention is to provide an optical transmission / reception apparatus which can reduce the number of optical elements as much as possible and at the same time use many common parts in the first and second optical modules, thereby reducing the manufacturing cost. .

1 is a diagram showing the configuration of an optical module on one side of an optical transmitting and receiving device according to an embodiment of the present invention;

2 is a diagram showing the configuration of an optical module on the other side of the optical transmitting and receiving device according to the embodiment of the present invention;

3 is a view showing a conventional optical transmitter and receiver.

※ Explanation of code in main part of drawing

11 laser diode 12 optical fiber

13 photodiode 14 light receiving element

15 light emitting device 20 optical module

21: collimation lens 22: collimation lens

23 collimation lens 24 optical filter

30: optical module 40: optical element

41: convex lens surface 42: lattice surface

43: substrate 50: transceiver element

51 substrate 52 laser diode

53: photodiode 54: filter

60: optical module 70: optical element

73: substrate 80: transceiver element

81: convex lens surface 81: substrate

82: the laser diode 83: photodiode

84: filter

In the present invention, in order to solve the above problems, the optical transmitting and receiving device is configured as follows. An optical transmission / reception apparatus according to the present invention connects a first optical module and a second optical module with an optical fiber, and transmits and receives signals between both modules, wherein the first optical module has a first wavelength? 1. A first light emitting device that emits light, a first light receiving device that receives light having a second wavelength λ2 from the optical fiber, and condenses the light of the first wavelength to the optical fiber and simultaneously receives the light of the second wavelength An optical member for condensing on the first light receiving element, and a first diffraction grating for emitting straight light of the first wavelength of light to the optical fiber side and emitting diffracted light of a second wavelength from the optical fiber to the first light receiving element side; The second optical module includes a second light emitting element emitting light of a second wavelength, a second light receiving element receiving light of a first wavelength from an optical fiber, and condensing light of the second wavelength on the optical fiber, Inducing light of the first wavelength And an optical transmission and reception device including a second member and a second diffraction grating for emitting straight light of the second wavelength light to the optical fiber side and emitting diffracted light of the first wavelength light from the optical fiber to the second light receiving element side. The pitch of the first diffraction grating was formed as P1, and the pitch P2 of the second diffraction grating was formed to be P1 × (λ1 / λ2).

According to the above invention, the number of collimator lenses can be reduced, and the diffraction angle of the light of the second wavelength [lambda] 2 by the first diffraction grating arranged in the first optical module and the second diffraction arranged in the second optical module Since the diffraction angle of the light of the first wavelength λ1 by the grating can be made the same, the box body and other members constituting the first and second modules can be used in common in both modules, It is possible to make the jig to be used in common.

In the optical transmitting and receiving device according to the present invention, the optical member provided in each module condenses the light from each light emitting element through the diffraction grating to the end surface of the optical fiber, and condenses the light from the optical fiber to the light receiving element via the diffraction grating. It is composed of a convex lens.

According to the optical transmitting / receiving device in which the optical member is composed of a convex lens, the light from the light emitting element can be condensed into the optical fiber and the light from the optical fiber can be condensed by the minimum number of optical elements.

In the optical transmitting and receiving device according to the present invention, the diffraction grating is formed integrally on one surface of the optical member.

In the present invention in which the diffraction grating is integrally formed on one side of the optical member, the optical member and the diffraction grating can be molded by one-time processing by mold molding, so that the processing time is reduced and the optical There is no need to assemble the member and the diffraction grating, so that the assembly effort is reduced and the position adjustment between both members is no longer performed.

EMBODIMENT OF THE INVENTION Hereinafter, embodiment which concerns on this invention is described based on an accompanying drawing. 1 and 2 show each optical module 30, 60 according to the embodiment of the optical transmission / reception apparatus according to the present invention.

The optical modules 30 and 60 constituting the optical transmission / reception apparatus according to the present example include a single-mode optical fiber 12 for the first optical module 30 shown in FIG. 1 and the second optical module 60 shown in FIG. 2. To combine.

As shown in FIG. 1, the 1st optical module 30 is comprised from the optical element 40 optically connected to the optical fiber 12 used in single mode, and the transmission / reception element 50. As shown in FIG.

The transmitting and receiving element 50 is a laser diode (LD) 52 which is a light emitting element emitting a laser light of a first wavelength (lambda = 1310 nm in this example) on the substrate 51, and a second wavelength (in this example). The photodiode (PD) 53 which receives light of (lambda) 2 = 1550 nm efficiently is arrange | positioned at the space | interval d, and the optical axis distance D with the optical element 40 is arrange | positioned. 1, the code | symbol 54 has shown the filter which blocks | blocks the light other than a necessity among the emitted light and incident light.

The optical element 40 has an aspherical convex lens surface 41 formed convexly on the optical fiber 12 side of the substrate 43. In addition, the optical element 40 enters the optical fiber 12 with light of the first wavelength (λ = 1310 nm) from the laser diode 52 on the side of the transceiver element side of the substrate 43. At the same time, the grating plane 42 is provided with the light of the second wavelength emitted from the optical fiber 12 (lambda = 1550 nm in this example) incident on the photodiode 53, which is a light receiving element.

The grating plane 42 determines the pitch p1 of the grating,

① 1310 nm light is transmitted as the 0th order transmitted light with high efficiency.

② It transmits light of 1550 nm as a first order diffracted light with high efficiency.

Under the conditions described above, for example, p1 = 20 mu m is selected.

This satisfies the above condition.

In addition, the convex lens surface and the lattice surface can select the characteristic as needed, and can also select the shape.

The second optical module is used in a single mode as shown in Fig. 2, and is composed of an optical element 70 and an optical transceiver 70 that are optically connected to the optical fiber 12 connected to the first optical module 30. have.

The transmission / reception element 80 is a laser diode (LD) 82 which is a light emitting element for emitting a laser light of a first wavelength (lambda = 1550 nm in this example) on the substrate 81, and a second wavelength (in this example). and a photodiode (PD) 83 that efficiently receives light of λ2 = 1310 nm, is arranged at an interval d (Fig. 2: same dimension as the first optical module), and an optical axis distance from the optical element 70. (D) (FIG. 2: same dimension as 1st optical module) is arrange | positioned. In addition, in FIG. 2, the code | symbol 84 has shown the filter which blocks | blocks the light other than a necessity among emitted light and incident light.

The optical element 70 has an aspherical convex lens surface 81 formed convexly on the optical fiber 12 side. In addition, the optical element 70 enters the optical fiber 12 with light of the first wavelength (λ = 1310 nm) from the laser diode 82 on the side of the transmitting / receiving element side of the substrate 73. At the same time, the grating plane 42 is provided with the light of the second wavelength emitted from the optical fiber 12 (lambda = 1550 nm in this example) incident on the photodiode 83 serving as the light receiving element.

The grating plane 42 determines the pitch p2 of the grating,

(1) The light of 1550 nm is transmitted as the 0th order transmitted light with high efficiency.

② 1310 nm light is transmitted as the first diffracted light with high efficiency.

Under the conditions described above, for example, p2 = p1 (1310/1550) ≒ 17 mu m is selected.

By selecting in this way, the convex lens surface and the lattice surface can select the characteristic as needed, and the shape can be selected. It can also be made to the same dimensions as the first optical module.

As mentioned above, although one Embodiment of this invention was described, this invention is not limited to the said Example, It can change in the range which does not deviate from the main point.

As described above, the optical transmission / reception apparatus according to the present invention can have the following excellent effects.

According to the present invention, the number of collimator lenses can be reduced, and the diffraction angle of the light of the second wavelength [lambda] 2 by the first diffraction grating arranged in the first optical module and the second diffraction arranged in the second optical module Since the diffraction angle of the light of the first wavelength λ1 by the grating can be made the same, the box body or other members constituting the first and second modules can be used in common for both modules, The jig can be made common.

In addition, according to the optical transmitting / receiving device in which the optical member is composed of a convex lens, the light from the light emitting element can be condensed into the optical fiber and the light from the optical fiber can be condensed by the minimum number of optical elements.

In the present invention in which the diffraction grating is integrally formed on one side of the optical member, the optical member and the diffraction grating can be molded by one-time processing by mold molding, so that the processing time is reduced, and the optical member and diffraction are reduced. No need for assembly with the grating, which reduces assembly effort and eliminates the need for position adjustment between the two members.

Claims (3)

In an optical transmitting and receiving device for connecting a first optical module and a second optical module with an optical fiber and transmitting and receiving signals between both modules, The first optical module includes a first light emitting device emitting light of a first wavelength λ1, a first light receiving device receiving light of a second wavelength λ2 from an optical fiber, and condensing light of the first wavelength on the optical fiber. At the same time, the optical member for condensing the light of the second wavelength to the first light receiving element, and the direct light of the light of the first wavelength is emitted to the optical fiber side and diffracted light of the second wavelength from the optical fiber to the first A first diffraction grating provided to the light receiving element side, The second optical module includes a second light emitting device emitting light of a second wavelength, a second light receiving device receiving light of a first wavelength from an optical fiber, and condensing light of the second wavelength on the optical fiber, An optical member for inducing light of one wavelength, and a second diffraction grating for emitting straight light of the second wavelength of light to the optical fiber side and emitting diffracted light of light of the first wavelength from the optical fiber to the second light receiving element side; Equipped, The pitch of the first diffraction grating is formed as P1, and the pitch (P2) of the second diffraction grating is formed to be P1 × (λ1 / λ2). The method of claim 1, The optical member provided in each module, The light from each light emitting element is condensed on the end surface of the optical fiber via a diffraction grating, An optical transmission / reception device comprising a convex lens for condensing light from an optical fiber to each light receiving element via a diffraction grating. The method according to claim 1 or 2, And a diffraction grating is integrally formed on one side of the optical member.