KR20220074037A - Optical Device Module and Optical Communication Network System Used the Same - Google Patents

Abstract

The present invention is a substrate; an optical waveguide on the substrate; a light source providing light into the optical waveguide; and a prism between the light source and the optical waveguide. The light source includes a lens.

Description

Optical Device Module and Optical Communication Network System Used the Same

The present invention relates to an optical module including a lens and an optical communication network system having the same.

In accordance with the trend toward miniaturization and high speed of electronic devices, research to increase the degree of integration of components constituting the electronic devices continues. In order to miniaturize and speed up electronic devices, it is required to reduce the size of the components and to transmit signals quickly between the components.

As one means for fast signal transmission between components, an optical communication technology between electronic devices is being applied. When the optical communication technology is applied to an electronic device, signal transmission is performed at a higher speed, and disadvantages of the existing signal transmission method, such as high resistance, high heat generation, and parasitic capacitance, can be alleviated.

Recently, research to introduce optical fiber optical communication technology, which is technically mature, to computers has been actively conducted. Typically, silicon photonics technology uses a silicon material as an optical waveguide to transmit an optical signal. In addition, research to directly utilize the existing optical fiber optical communication technology by inserting the optical fiber into the PCB board of the computer is being actively conducted.

An object of the present invention is to provide an optical module capable of emitting parallel light from a light source and an optical communication network system having the same.

The present invention is a substrate; an optical waveguide on the substrate; a light source providing light into the optical waveguide; and a prism between the light source and the optical waveguide, wherein the light source provides an optical module including a lens.

The lens may include a flat base portion, and a hemispherical protrusion that protrudes from the base portion toward the prism.

The light source may include an adhesive layer covering the lens, and a light transmitting part on the adhesive layer.

The light source may further include a light generating unit emitting the light toward the lens, and the lens may satisfy [Equation 1] below.

[Equation 1]

F tan ^-1 (1/2 θ1) < R

The radius of the lens may be 1㎛ to 100㎛.

The refractive index of the lens may be 1.65 to 2.5, and the refractive index of the adhesive layer may be 1.3 to 1.55.

The lens may include at least one of SiC, GaN, Si ₃ N ₄ , TiN, LiNbO ₃ , TiO ₂ , ZnSe, and Polyimide.

The prism may further include an anti-reflection film covering the lower surface and the inclined surface.

The light passing through the lens may be parallel light.

The present invention is a substrate; an optical waveguide on the substrate; a filter on the optical waveguide; a prism on the filter; and a light source on the inclined surface of the prism.

The filter may be a wavelength division multiplexing filter.

The filter may include an upper mirror, a lower mirror, and a spacer between the upper mirror and the lower mirror.

A path through which the light emitted from the light source passes through the upper mirror, the spacer, and the lower mirror may have the same length.

The upper mirror and the lower mirror may have a symmetrical structure with respect to the spacer.

and a buffer layer between the filter and the optical waveguide, wherein the upper mirror includes a first filter film in contact with the prism and a second filter film in contact with the spacer, and the lower mirror includes a third filter film in contact with the spacer. and a fourth filter film in contact with the buffer layer, wherein the first filter film and the fourth filter film have the same thickness and refractive index, and the second filter film and the third filter film have the same thickness and refractive index.

A refractive index of the spacer may be the same as a refractive index of the first filter layer.

The present invention provides a substrate comprising: a substrate having a sub control region, a connection region, and a sub unit cell region; a first light source and a first detector on the sub-control area; a second light source and a second detector on the sub-unit cell area; a first optical waveguide connecting the first light source and the second detector and a second optical waveguide connecting the second light source and the first detector; and a first prism between the first light source and the first optical waveguide, and a second prism between the second light source and the second optical waveguide.

The apparatus may further include a first filter between the first prism and the first optical waveguide, and a second filter between the second prism and the second optical waveguide.

The first and second prisms may further include anti-reflection layers covering a lower surface and an inclined surface of each of the prisms.

Each of the first light source and the second light source may include a lens.

In the optical module and the optical communication network system having the same according to the present invention, the light source includes a lens, so that parallel light can be emitted from the light source.

1 is a diagram schematically illustrating an optical communication network system according to an embodiment of the present invention.
2 is a diagram for describing sub-control parts and sub-unit cell parts in more detail.
3 is a cross-sectional view illustrating an optical module according to an embodiment of the present invention.
4 is a cross-sectional view for explaining a condition for the light source of FIG. 3 to emit parallel light.
5 is a cross-sectional view of an optical module according to an embodiment of the present invention.
6A is a cross-sectional view of an optical module according to an embodiment of the present invention.
FIG. 6B is an enlarged view of area A of FIG. 6A .
7A is a graph showing reflectivity of a mirror.
7B is a graph showing the transmittance of the filter using the mirror of FIG. 7A.
8 is a view for explaining a function of an optical module including a filter.
9 is a cross-sectional view illustrating an optical module according to an embodiment of the present invention.

Advantages and features of the present invention, and methods for achieving them, will become apparent with reference to the embodiments described below in detail in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but may be implemented in various different forms, and only these embodiments allow the disclosure of the present invention to be complete, and common knowledge in the technical field to which the present invention pertains. It is provided to fully inform the possessor of the scope of the invention, and the present invention is only defined by the scope of the claims. Like reference numerals refer to like elements throughout.

The terminology used herein is for the purpose of describing the embodiments and is not intended to limit the present invention. In this specification, the singular also includes the plural unless specifically stated otherwise in the phrase. As used herein, 'comprises' and/or 'comprising' refers to the presence of one or more other components, steps, operations and/or devices mentioned. or addition is not excluded. Hereinafter, embodiments of the present invention will be described in detail.

1 is a diagram schematically illustrating an optical communication network system according to an embodiment of the present invention.

Referring to FIG. 1 , an optical communication network system according to an embodiment of the present invention includes main control parts 20 , sub control parts 30 , sub unit cell parts 40 , and optical waveguides 50 . can do. The optical waveguides 50 may connect the main control parts 20 , the sub control parts 30 , and the sub unit cell parts 40 to each other. The main control parts 20 may output a control signal for controlling the sub control parts 30 and the sub unit cell parts 40 , and receive a response signal. The sub control parts 30 may communicate with the main control parts 20 and control the sub unit cell parts 40 . One sub control part 30 and 16 sub unit cell parts 40 may constitute unit cell parts 60 , respectively. When the unit cell parts 60 are composed of 16 , the unit cell parts 60 may include 16 ² sub-unit cell parts 40 . In addition, one main control part 20 and 16 unit cell parts 60 may constitute upper unit cells 70 . Although not shown, the 16 upper unit cell parts 70 may include 16 ³ sub unit cell parts 40 . The upper unit cell 70 and super main control parts (not shown) may constitute a high-dimensional unit cell. Accordingly, as the dimension of the unit cell parts 60 increases, the optical communication network system of the present invention may include the sub-unit cell parts 40 designed with a higher-order number of 16 .

The sub control parts 30 transmit the optical signal of the sub unit cell parts 40 to other sub unit cell parts 40, other unit cells 60 or higher unit cells within the unit cell part 60 of the same group. It can be decided whether to output to (70). The main control parts 20 , the sub control parts 30 , and the sub unit cell parts 40 may perform mutual photoelectric conversion of an optical signal and an electrical signal, respectively.

2 is a diagram for describing sub-control parts and sub-unit cell parts in more detail.

1 and 2 , the sub control parts 30 may include light emitting arrays (LD array) and light receiving arrays (PD array). The light emitting array (LD array) of the sub control parts 30 may include first light sources 72 , and the light receiving array (PD array) may include first detectors 74 . The sub unit cell portions 40 may include a portion of a light emitting array (LD array) and a portion of a light receiving array (PD array). The sub unit cell portions 40 may include a second light source 78 , and may include a second detector 76 . The first light source 72 and the second light source 78 may include a vertical cavity surface emitting laser (VCSEL) or a laser diode. The first detector 74 and the second detector 76 may include photodiodes. The first light source 72 and the second detector 76 may be connected by a first optical waveguide 52 . The first light source 72 , the first optical waveguide 52 , and the second detector 76 may be a first communication line. In addition, the second optical waveguide 54 may connect the first detector 74 and the second light source 78 . Likewise, the first detector 74 , the second optical waveguide 54 , and the second light source 78 may be a second communication line. The first optical waveguide 52 and the second optical waveguide 54 may connect the sub control parts 30 and the sub unit cell parts 40 without intersecting each other.

The first light source 72 , the first detector 74 , the second light source 78 , and the second detector 76 are optical elements. The optical elements may be combined with optical waveguides to constitute an optical module. The optical waveguide 50 may connect optical modules. The sub unit cell portions 40 may have a plurality of optical modules for transmitting and receiving optical signals.

Hereinafter, an embodiment of an optical module capable of maximizing the optical coupling efficiency will be described.

3 is a cross-sectional view illustrating an optical module according to an embodiment of the present invention.

Referring to FIG. 3 , the optical module includes a substrate 100 , a lower clad layer 110 , an optical waveguide 120 , an upper clad layer 130 , a buffer layer 140 , a prism 150 , and a light source 200 . can do.

The substrate 100 may include crystalline silicon. Crystalline silicon may have a refractive index of about 3.45. Although not shown, the substrate 100 may have a sub control region, a connection region, and a sub unit cell region. The sub control region may correspond to the sub control cell portions 30 of FIGS. 1 and 2 . The sub-unit cell region may correspond to the sub-unit cell portions 40 of FIGS. 1 and 2 . The connection region may be a region between the sub control region and the sub unit cell region.

A lower clad layer 110 may be provided on the substrate 100 . The lower clad layer 110 may include silicon oxide. Silicon oxide may have a refractive index of about 1.45.

The optical waveguide 120 may be provided on the lower clad layer 110 . The lower clad layer 110 may have a lower refractive index than the optical waveguide 120 . The optical waveguide 120 may have a lower refractive index than the substrate 100 . The optical waveguide 120 may include silicon nitride or silicon oxy nitride. Silicon nitride may have a refractive index of about 2.0. Silicon oxynitride may have an index of refraction of about 1.7. The optical waveguide 120 may correspond to the optical waveguide 50 of FIGS. 1 and 2 .

The upper surface of the optical waveguide 120 may be divided into a first portion and a second portion. The upper clad layer 130 may cover the first portion of the upper surface of the optical waveguide 120 . The upper clad layer 130 may expose a second portion of the upper surface of the optical waveguide 120 . The refractive index of the upper clad layer 130 may be lower than that of the optical waveguide 120 . The upper clad layer 130 may include silicon oxide.

The buffer layer 140 may cover the second portion of the upper surface of the optical waveguide 120 . In other words, the buffer layer 140 may cover the upper surface of the optical waveguide 120 exposed by the upper clad layer 130 . The buffer layer 140 may have a higher refractive index than the optical waveguide 120 . The buffer layer 140 may include an index matching oil or adhesive having a refractive index of about 1.7 to 2.1.

The prism 150 may be disposed on the buffer layer 140 . The lower surface 151 of the prism 150 may contact the buffer layer 140 . The buffer layer 140 may prevent the inflow of air between the prism 150 and the optical waveguide 120 . When air is introduced between the prism 150 and the optical waveguide 120 , the light transmission efficiency between the prism 150 and the optical waveguide 120 may be reduced. The prism 150 may have a higher refractive index than the buffer layer 140 . The prism 150 may have a wedge shape with an inclined surface 152 . An inclination angle of the prism 150 may be defined as a first angle θ1 . The prism 150 may include crystalline silicon or gallium phosphide (GaP). Gallium phosphide may have a refractive index of about 3.05.

The light source 200 may be in contact with the inclined surface 152 of the prism 150 . The light source 200 of this embodiment may correspond to the first light source 72 or the second light source 78 of FIGS. 1 and 2 . Instead of the light source 200, a detector corresponding to the first detector 74 or the second detector 76 of FIGS. 1 and 2 may be provided.

The light source 200 may provide the laser light L to the optical waveguide 120 . The light source 200 may include a light generating unit 210 , a lens 220 , an adhesive layer 230 , and a light transmitting unit 240 .

The light generator 210 may generate and emit laser light L. The light generator 210 may be a vertical cavity surface emitting laser (VCSEL) or a laser diode. The laser light L emitted from the light generator 210 may have a second angle θ2 as a radiation angle. For example, the second angle θ2 may be 20 to 40 degrees. The light generator 210 may include an opening 211 , and the laser light L may be emitted from the opening 211 .

A lens 220 may be provided on the light generator 210 . The lens 220 may include a base part 221 and a protrusion part 222 . The base part 221 may have a flat plate shape. The protrusion 222 may have a hemispherical shape. The base part 221 may be provided on the light generator 210 , and the protrusion 222 may protrude from the base part 221 toward the prism 150 . The lens 220 may have a refractive index of 1.65 to 2.5. The lens 220 may include at least one of SiC, GaN, Si ₃ N ₄ , TiN, LiNbO ₃ , TiO ₂ , ZnSe, and Polyimide.

An adhesive layer 230 may be provided on the lens 220 . The adhesive layer 230 may cover the lens 220 . In other words, the adhesive layer 230 may cover the upper surface 221a of the base portion 221 of the lens 220 and the upper surface 222a of the protrusion 222 of the lens 220 . The adhesive layer 230 may have a refractive index of 1.3 to 1.55. The adhesive layer 230 may include an optical adhesive.

The light transmitting part 240 may be provided on the adhesive layer 230 . The light transmitting part 240 may include glass or quartz. Although the light transmitting part 240 is shown to be in contact with the protrusion 222 of the lens 220, the present invention may not be limited thereto. In other words, the light transmitting portion 240 may be spaced apart from the protrusion 222 of the lens 220 by the adhesive layer 230 .

When explaining the operation of the optical module according to the embodiment of the present invention, the laser light L generated by the light generating unit 210 of the light source 200 may pass through the lens 220 and the adhesive layer 230 . While passing through the lens 220 and the adhesive layer 230 , the radiation angle of the laser light L may decrease. Accordingly, the laser light L passing through the light transmitting part 240 may be parallel light. In other words, the radiation angle of the laser light L passing through the light transmitting part 240 may be 0 degrees.

The laser light L passing through the light transmitting part 240 may be vertically incident on the inclined surface 152 of the prism 150 and pass through the prism 150 . The laser light L passing through the prism 150 may form a third angle θ3 with the lower surface 151 of the prism 150 . The third angle θ3 may correspond to an inclination angle of the prism 150 . In other words, the sum of the first angle θ1 and the third angle θ3 may be 90 degrees.

The laser light L passing through the prism 150 may pass through the buffer layer 140 and be incident into the optical waveguide 120 . The laser light L incident into the optical waveguide 120 may be reflected by the lower clad layer 110 and the upper clad layer 130 , and may travel along the optical waveguide 120 .

If the light passing through the light transmitting part 240 of the light source 200 is not parallel light, the laser light L may not be focused on the optical waveguide 120 through the prism 150 and the buffer layer 140 . For example, when the radiation angle of the laser light L passing through the light transmitting part 240 is 2 degrees or more, the laser light L may not be focused on the optical waveguide 120 . In the present invention, the laser light L emitted from the light source 200 may be a parallel light, and the laser light L may be focused on the optical waveguide 120 .

When explaining the method of manufacturing the optical module according to the embodiment of the present invention, the adhesive layer 230 may be formed on the lens 220 , and the light transmitting part 240 may be attached to the adhesive layer 230 . Next, the light source 200 may be manufactured by attaching the lens 220 to the light generating unit 210 . Next, when the light source 200 is attached to the prism 150 and the prism 150 is attached to the buffer layer 140 , the optical module may be manufactured.

4 is a view for explaining a condition for the light source of FIG. 3 to emit parallel light.

Referring to FIG. 4 , the laser light L emitted from the light generator 210 of the light source 200 may have a second angle θ2 as a radiation angle. The second angle θ2 may be 20 degrees to 40 degrees. The laser light L passing through the light transmitting part 240 of the light source 200 may be parallel light. In other words, the radiation angle of the laser light L passing through the light transmitting part 240 of the light source 200 may be 0 degrees.

In order for the laser light L passing through the light transmitting part 240 to become a parallel light, the condition according to [Equation 1] below must be satisfied.

In [Equation 1], F is the focal length of the protrusion 222 of the lens 200, R is the radius of the protrusion 222 of the lens 200, and θ2 is the emitted light from the light generating unit 210. It is the radiation angle (second angle) of the laser light L. In [Equation 1], the first distance D1 may be defined by the focal length F and the second angle θ2.

The focal length F of the protrusion 222 of the lens 200 may be derived according to [Equation 2] below.

In Equation 2, n1 is the refractive index of the lens 220 , and n2 is the refractive index of the adhesive layer 230 .

When the condition of [Equation 1] is satisfied and the first distance D1 is smaller than the radius R of the protrusion 222 of the lens 220, the laser light L passing through the light transmitting part 240 This can be parallel light. When the condition of [Equation 1] is not satisfied and the first distance D1 is greater than the radius R of the protrusion 222 of the lens 220, the laser light L passing through the light transmitting part 240 This cannot be parallel light.

Referring to [Equation 1] and [Equation 2], the radius R of the protrusion 222 of the lens 220, the refractive index n1 of the lens 220, and the refractive index n2 of the adhesive layer 230 can be appropriately set to satisfy the condition according to [Equation 1]. For example, when the second angle θ2 is 30 degrees, the refractive index n2 of the adhesive layer 230 is 1.46, and the radius R of the protrusion 222 of the lens 220 is 15 μm, the lens ( When the refractive index n1 of 220 is set to 1.72 or more, the laser light L passing through the light transmitting unit 240 may become parallel light. When the lens 220 includes polyimide, the refractive index n1 may be 1.72.

The radius R of the protrusion 222 of the lens 220 may be 1 μm to 100 μm, the refractive index n1 of the lens 220 may be 1.65 to 2.5, and the refractive index n2 of the adhesive layer 230 . may be 1.3 to 1.55.

5 is a cross-sectional view of an optical module according to an embodiment of the present invention. The optical module according to this embodiment is similar to the optical module according to FIG. 3 except as described below.

Referring to FIG. 5 , the optical module may further include an anti-reflection film 160 . The anti-reflection layer 160 may include a first portion 161 and a second portion 162 .

The first portion 161 of the anti-reflection layer 160 may be provided on the lower surface 151 of the prism 150 . The second portion 162 of the anti-reflection layer 160 may be provided on the inclined surface 152 of the prism 150 . A thickness of the first part 161 and a thickness of the second part 162 may be substantially the same. In other words, the anti-reflection layer 160 may conformally cover the lower surface 151 and the inclined surface 152 of the prism 150 .

The anti-reflection layer 160 may include first reflective layers and second reflective layers that are alternately stacked. The thickness of the first reflective layers and the thickness of the second reflective layers may be different from each other. A material included in the first reflective layers and a material included in the second reflective layers may be different from each other. The refractive index of the first reflective layers and the refractive index of the second reflective layers may be different from each other.

The prism 150 and the buffer layer 140 may be spaced apart from each other with the first portion 161 of the anti-reflection layer 160 interposed therebetween. The prism 150 and the light transmitting portion 240 of the light source 200 may be spaced apart from each other with the second portion 162 of the anti-reflection film 160 interposed therebetween.

6A is a cross-sectional view of an optical module according to an embodiment of the present invention. FIG. 6B is an enlarged view of area A of FIG. 6A . The optical module according to this embodiment is similar to the optical module according to FIG. 3 except as described below.

6A and 6B , the optical module may further include a filter 170 . The filter 170 may be a wavelength division multiplexing (WDM) filter. The filter 170 may be provided on the lower surface 151 of the prism 150 . The prism 150 and the buffer layer 140 may be spaced apart from each other with the filter 170 interposed therebetween.

The filter 170 may include an upper mirror 171 , a spacer 172 , and a lower mirror 173 . The spacer 172 may be disposed between the upper mirror 171 and the lower mirror 173 . The upper mirror 171 may be in contact with the lower surface 151 of the prism 150 . The lower mirror 173 may be in contact with the upper surface of the buffer layer 140 .

The upper mirror 171 may include a pair of a first filter film 171a and a second filter film 171b. The first and second filter layers 171a and 171b may include different materials. For example, the first filter layer 171a may include TiO ₂ , and the second filter layer 171b may include Ta ₂ O ₅ . The refractive indices of the first and second filter layers 171a and 171b may be different from each other. The thicknesses of the first and second filter layers 171a and 171b may be different from each other. The first filter film 171a may contact the prism 150 , and the second filter film 171b may contact the spacer 172 .

Although the upper mirror 171 is illustrated as including a pair of a first filter film 171a and a second filter film 171b, it may not be limited thereto. The upper mirror 171 may include a plurality of pairs of a first filter film 171a and a second filter film 171b. In this case, the first filter films 171a and the second filter films 171b may be alternately provided.

The spacer 172 may include the same material as the first filter layer 171a. As shown, when the upper mirror 171 includes a pair of the first filter film 171a and the second filter film 171b, the thickness of the spacer 172 is the thickness of the first filter film 171a. can be twice the Unlike the illustration, for example, when the upper mirror 171 includes two pairs of the first filter film 171a and the second filter film 171b, the thickness of the spacer 172 is the first filter film ( 171a) may be four times.

The lower mirror 173 may include a third filter film 173a and a fourth filter film 173b. The third and fourth filter layers 173a and 173b may include different materials. The third filter film 173a may include the same material as the second filter film 171b of the upper mirror 171 . The fourth filter film 173b may include the same material as the first filter film 171a of the upper mirror 171 . Thicknesses of the third and fourth filter layers 173a and 173b may be different from each other. The thickness of the third filter film 173a may be the same as the thickness of the second filter film 171b of the upper mirror 171 . The thickness of the fourth filter film 173b may be the same as the thickness of the first filter film 171a of the upper mirror 171 . The third filter film 173a may contact the spacer 172 , and the fourth filter film 173b may contact the buffer layer 140 .

The lower mirror 173 is illustrated as including a pair of a third filter film 173a and a fourth filter film 173b, but may not be limited thereto. The lower mirror 173 may include a plurality of pairs of a third filter film 173a and a fourth filter film 173b. In this case, the third filter films 173a and the fourth filter films 173b may be alternately provided.

The upper mirror 171 and the lower mirror 173 may have a symmetrical structure with respect to the spacer 172 .

The filter 170 may pass laser light of a specific wavelength. Referring to FIG. 6B , for example, the filter 170 may pass laser light having a first wavelength λ1 and reflect laser light having a wavelength different from that of the first wavelength λ1 . When the laser light of the first wavelength λ1 passes through the prism 150 and is incident on the filter 170 , it may pass through the upper mirror 171 , the spacer 172 , and the lower mirror 173 . While passing through the upper mirror 171 , the spacer 172 , and the lower mirror 173 , the laser light may be refracted.

In the first filter layer 171a of the upper mirror 171, the length of the path through which the laser light passes may be 1/4 times the first wavelength λ1. In the second filter layer 171b of the upper mirror 171, the length of the path through which the laser light passes may be 1/4 times the first wavelength λ1. The refractive index and thickness of the first filter layer 171a and the second filter layer 171b may be set so that the length of the path through which the laser light passes is 1/4 times the first wavelength λ1. Consequently, the length of the path through which the laser light passes in the upper mirror 171 may be 1/2 times of the first wavelength λ1.

Contrary to the illustration, for example, when the upper mirror 171 includes two pairs of the first filter film 171a and the second filter film 171b, the laser light passes through the upper mirror 171 . The length may be equal to the first wavelength λ1.

In the spacer 172 , the length of the path through which the laser light passes may be 1/2 times the first wavelength λ1 . In other words, the length of the path through which the laser light passes may be the same in the spacer 172 and the upper mirror 171 . The refractive index and thickness of the spacer 172 may be set so that the length of the path through which the laser light passes is 1/2 times the first wavelength λ1.

In the third filter layer 173a of the lower mirror 173 , the length of the path through which the laser light passes may be 1/4 times the first wavelength λ1 . In the fourth filter layer 173b of the lower mirror 173 , the length of the path through which the laser light passes may be 1/4 times the first wavelength λ1 . The refractive index and thickness of the third filter layer 173a and the fourth filter layer 173b may be set so that the length of the path through which the laser light passes is 1/4 times the first wavelength λ1 . As a result, the length of the path through which the laser light passes in the lower mirror 173 may be 1/2 the length of the first wavelength λ1.

Contrary to the illustration, for example, when the lower mirror 173 includes two pairs of the third filter film 173a and the fourth filter film 173b, the length of the path through which the laser light passes is equal to the first wavelength ( λ1) may be the same.

The filter 170 having the exemplarily described structure may pass laser light having a first wavelength λ1 and reflect laser light having a wavelength different from that of the first wavelength λ1.

7A is a graph showing reflectivity of a mirror. 7B is a graph showing the transmittance of the filter using the mirror of FIG. 7A.

Referring to FIG. 7A , reflectivity when laser light is incident on a mirror (upper mirror or lower mirror) including four pairs of a first filter film and a second filter film can be confirmed. In the mirror, the refractive index and thickness of the first filter film and the second filter film are set so that the length of the path through which the laser light passes through the first filter film and the second filter film is 1/4 times of 850 nm. In FIG. 7A , it can be seen that the reflectivity of the laser light is relatively high around 850 nm.

Referring to FIG. 7B , the transmittance when the laser light is incident on a filter using the mirror of FIG. 7A as an upper mirror and a lower mirror can be confirmed. The filter is set such that the length of the path through which the laser light passes through the upper mirror is twice that of 850 nm, the length of the path through the spacer is twice that of 850 nm, and the length of the path through the lower mirror is twice that of 850 nm. It can be seen that the laser light has a relatively high transmittance at 850 nm.

8 is a view for explaining a function of an optical module including a filter.

Referring to FIG. 8 , in the optical module according to the present embodiment, first to fourth prisms 150a , 150b , 150c , and 150d may be provided on the optical waveguide 120 . The first to fourth prisms 150a , 150b , 150c , and 150d may be connected to the optical waveguide 120 through the buffer layers 140 . A first filter 170a may be provided under the first prism 150a, a second filter 170b may be provided under the second prism 150b, and a third filter 170b may be provided under the third prism 150c. A filter 170c may be provided, and a fourth filter 170d may be provided under the fourth prism 150d. The first and fourth filters 170a and 170d may pass laser light having a second wavelength λ2 and reflect laser light having a wavelength different from that of the second wavelength λ2. The second and third filters 170b and 170c may pass laser light having a third wavelength λ3 and reflect laser light having a wavelength different from that of the third wavelength λ3.

The first light source 200a may be provided on the first prism 150a, the second light source 200b may be provided on the second prism 150b, and the first light source 200b may be provided on the third prism 150c. A detector 300a may be provided, and a second detector 300b may be provided on the fourth prism 150d.

Laser light of the second wavelength λ2 may be emitted from the first light source 200a. The first filter 170a may pass the laser light of the second wavelength λ2. The laser light of the second wavelength λ2 may pass through the first filter 170a to be incident on the optical waveguide 120 , and may travel within the optical waveguide 120 .

While traveling in the optical waveguide 120 , the laser light of the second wavelength λ2 may pass under the second and third filters 170b and 170c. Since the laser light of the second wavelength λ2 is reflected by the second and third filters 170b and 170c, the laser light of the second wavelength λ2 passes through the second filter 170b and the second prism 150b ) may not be emitted, and may not pass through the third filter 170c and may not be emitted above the third prism 150c. The laser light of the second wavelength λ2 that has passed under the second and third filters 170b and 170c along the optical waveguide 120 passes through the fourth filter 170d to be emitted above the fourth prism 150d. can

The laser light of the third wavelength λ3 emitted from the second light source 200b sequentially passes through the second filter 170b, the optical waveguide 120, and the third filter 170c and is above the third prism 150c. can be emitted.

As described above, the first to fourth filters 170a, 170b, 170c, and 170d are provided under the first and second light sources 200a and 200b and the first and second detectors 300a and 300b, The path of the laser light may vary depending on the wavelength.

9 is a cross-sectional view illustrating an optical module according to an embodiment of the present invention. The optical module according to this embodiment is similar to the optical module according to FIG. 3 except as described below.

Referring to FIG. 9 , the optical module may further include a connection electrode 180 , a wire 190 , and a case 400 . The connection electrode 180 may be provided on the upper clad layer 130 . The connection electrode 180 may contact the buffer layer 140 on the upper clad layer 130 . The upper surface of the connection electrode 180 and the upper surface of the buffer layer 140 may form a coplanar surface. Although not shown, the connection electrode 180 may be electrically connected to an external electric circuit.

The light generator 210 of the light source 200 may further include an internal electrode 212 . The internal electrode 212 and the connection electrode 180 may be electrically connected by a wire 190 .

The case 400 may include an empty space therein. The light source 200 , the prism 150 , and the wire 190 may be accommodated in the empty space. In other words, the light source 200 , the prism 150 , and the wire 190 may be sealed by the case 400 . The light source 200 , the prism 150 , and the wire 190 may be protected from external forces by the case 400 . The first portion of the case 400 may be in contact with the upper surface of the buffer layer 140 . The second portion of the case 400 may be in contact with the upper surface of the connection electrode 180 . The connection electrode 180 may be provided between the case 400 and the upper cladding layer 130 to connect the empty space inside the case 400 and the external space.

As mentioned above, although embodiments of the present invention have been described with reference to the accompanying drawings, those of ordinary skill in the art to which the present invention pertains can practice the present invention in other specific forms without changing its technical spirit or essential features. You will understand that there is Therefore, it should be understood that the embodiments described above are illustrative in all respects and not restrictive.

100: substrate
120: optical waveguide
140: buffer layer
200: light source

Claims (20)

Board;
an optical waveguide on the substrate;
a light source providing light into the optical waveguide; and
a prism between the light source and the optical waveguide;
The light source is an optical module including a lens.
According to claim 1,
The lens is an optical module including a flat base portion, and a hemispherical protrusion protruding from the base portion toward the prism.
According to claim 1,
The light source is an optical module comprising an adhesive layer covering the lens, and a light transmitting portion on the adhesive layer.
According to claim 1,
The light source further comprises a light generating unit for emitting the light toward the lens,
The lens is an optical module that satisfies [Equation 1] below.
[Equation 1]
F tan ^-1 (1/2 θ1) < R
(In Equation 1, F is the focal length of the lens, θ1 is the radiation angle of the light emitted from the light generator, and R is the radius of the lens).
According to claim 1,
The radius of the lens is 1㎛ to 100㎛ optical module.
4. The method of claim 3,
The refractive index of the lens is 1.65 to 2.5,
The refractive index of the adhesive layer is 1.3 to 1.55 optical module.
According to claim 1,
The lens is an optical module comprising at least one of SiC, GaN, Si ₃ N ₄ , TiN, LiNbO ₃ , TiO ₂ , ZnSe, and Polyimide.
According to claim 1,
The optical module further comprising an anti-reflection film covering the lower surface and the inclined surface of the prism.
According to claim 1,
The light passing through the lens is a parallel light optical module.
Board;
an optical waveguide on the substrate;
a filter on the optical waveguide;
a prism on the filter; and
An optical module comprising a light source on the inclined surface of the prism.
11. The method of claim 10,
The filter is an optical module that is a wavelength division multiplexing filter.
11. The method of claim 10,
The filter is an optical module comprising an upper mirror, a lower mirror, and a spacer between the upper mirror and the lower mirror.
13. The method of claim 12,
An optical module in which the length of a path through which the light emitted from the light source passes through the upper mirror, the spacer, and the lower mirror is the same.
13. The method of claim 12,
The upper mirror and the lower mirror have a symmetrical structure with respect to the spacer.
13. The method of claim 12,
Further comprising a buffer layer between the filter and the optical waveguide,
The upper mirror includes a first filter film in contact with the prism and a second filter film in contact with the spacer,
The lower mirror includes a third filter film in contact with the spacer and a fourth filter film in contact with the buffer layer,
The first filter film and the fourth filter film have the same thickness and refractive index,
The second filter film and the third filter film have the same thickness and refractive index.
16. The method of claim 15,
The refractive index of the spacer is the same as the refractive index of the first filter film optical module.
a substrate having a sub control region, a connection region, and a sub unit cell region;
a first light source and a first detector on the sub-control area;
a second light source and a second detector on the sub-unit cell area;
a first optical waveguide connecting the first light source and the second detector and a second optical waveguide connecting the second light source and the first detector; and
and a first prism between the first light source and the first optical waveguide, and a second prism between the second light source and the second optical waveguide.
18. The method of claim 17,
The optical communication network system further comprising: a first filter between the first prism and the first optical waveguide; and a second filter between the second prism and the second optical waveguide.
18. The method of claim 17,
The optical communication network system further comprising anti-reflection films covering a lower surface and an inclined surface of each of the first and second prisms.
18. The method of claim 17,
Each of the first light source and the second light source includes a lens.

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