Optical printed circuit board, apparatus and method for manufacturing same

An optical printed circuit board includes a substrate, a first cladding layer, a core layer, and a second cladding layer. The first cladding layer is formed on the substrate and defines a receiving groove. The core layer is received in the receiving groove. The second cladding layer is formed on the core layer. The refractive index of the core layer is greater than that of the first cladding layer and that of the second cladding layer. The core layer includes a bottom surface, a first refractive surface, and a second refractive surface. An included angle between the bottom surface and the first refractive surface is about 135 degrees. An included angle between the bottom surface and the second refractive surface is about 135 degrees.

BACKGROUND

1. Technical Field

The present disclosure relates to an optical printed circuit board (OPCB), an apparatus and a method for manufacturing the OPCB.

2. Description of Related Art

OPCBs include a cladding layer and a core layer received in the cladding layer. The core layer is used for transmitting optical signals. In related art, the core layer needs to be manually assembled in the cladding layer, which will reduce the manufacturing efficiency of the OPCBs.

Therefore, it is desirable to provide an OPCB, an apparatus and a method for manufacturing the OPCB that can overcome the above-mentioned limitations.

DETAILED DESCRIPTION

FIG. 1andFIG. 2illustrate an OPCB100in accordance with a first embodiment. The OPCB100includes a substrate110, a first cladding layer120, a core layer130, and a second cladding layer140. The first cladding layer120, the core layer130, and the second cladding layer140are made of transparent material.

The first cladding layer120is formed on the substrate110and defines a receiving groove121. The receiving groove121has a loading surface123, a first inclined surface124, and a second inclined surface125. The first inclined surface124and the second inclined surface125are positioned at opposite ends of the loading surface123. The included angle between the first inclined surface124and the loading surface123is about 135 degrees. The included angle between the second inclined surface125and the loading surface123is also about 135 degrees.

The core layer130is received in the receiving groove121. In this embodiment, the core layer130is coupled with the receiving groove121and includes a bottom surface130a, a first reflecting surface131, and a second reflecting surface132. The second reflecting surface132and the first reflecting surface131are positioned at opposite ends of the bottom surface130a. The included angle α between the first reflecting surface131and the bottom surface130ais about 135 degrees. The included angle β between the second reflecting surface132and the bottom surface130ais also about 135 degrees. The bottom surface130ais in contact with the loading surface123. The first reflecting surface131is in contact with the first inclined surface124. The second reflecting surface132is in contact with the second inclined surface125.

The second cladding layer140is formed on the core layer130and cooperates with the first cladding layer120to seal the core layer130therebetween.

The first cladding layer120and the second cladding layer140are made of low refractive index material, such as the following materials without light sensitive groups: polyacrylate, polysiloxane, polyimide, polycarbonate, fluorinated polymer, or mixture of at least two above materials. In this embodiment, the material of the first cladding layer120is the same as the material of the second cladding layer140. In another embodiment, the material of the first cladding layer120is different from the material of the second cladding layer140.

The refractive index of the core layer130is greater than the refractive index of the first cladding layer120and the refractive index of the second cladding layer140. The core layer130is made of high refractive index material, such as the following materials with light sensitive groups: polyacrylate, polysiloxane, polyimide, polycarbonate, fluorinated polymer, or mixture of at least two above materials.

In use, a light emitting module (not shown) and a light receiving module (not shown) are positioned on a surface of the second cladding layer140away from the substrate110, and these are respectively aligned with the first reflecting surface131and the second reflecting surface132. Optical signals from the light emitting module pass through the second cladding layer140, then enter the core layer130, and are reflected by the first reflecting surface131and the second reflecting surface132, and then enter the second cladding layer140again, at last being received by the light receiving module.

Referring toFIG. 3, an apparatus200for manufacturing the OPCB100includes a first roller pressing device210, a second roller pressing device260, and a third roller pressing device290.

The first roller pressing device210is used for forming a first cladding layer120with the receiving groove121on the substrate110, and includes a first pressing roller211, a first auxiliary roller212, a first feeder213, and a first drying element218. Referring also toFIGS. 4&5, a rolling surface211aof the first pressing roller211carries a master first impression pattern220to impress a shape matching that of the receiving groove121. The first impression pattern220includes a first molding groove221and a first protrusion222. The first molding groove221has a first molding surface221aand two opposite second molding surfaces221b. The first molding surface221ais perpendicularly connected to the two second surfaces221b. The first protrusion222is positioned on the middle of the first molding surface221a, and has a first side surface223, a second side surface224, and a connecting surface225. The second side surface224is opposite to the first side surface223. The connecting surface225is connected to the first side surface223and the second side surface224, and is substantially parallel to the first molding surface221a. An included angle of the first side surface223and the connecting surface225is about 135 degrees. An included angle of the second side surface224and the connecting surface225is also about 135 degrees. In other embodiments, the two second molding surfaces221bcan be other than perpendicular to the first molding surface221a, and the connecting surface225can be other than parallel to the first molding surface221a.

The first auxiliary roller212has a smooth outer rolling surface212a. The first auxiliary roller212is under the first pressing roller211, and is at a predetermined distance from the first pressing roller211to form a molding channel230. The molding channel230has an inlet231and an outlet232. The substrate110enters the molding channel230from the inlet231, and leaves the molding channel230through the outlet232. The first feeder213is used for feeding a first cladding layer forming solvent to the substrate110. The first cladding layer forming solvent is a solvent for forming the first cladding layer120.

The first pressing roller211and the first auxiliary roller212rotate in opposite directions, and cooperate to press the substrate110to form a first cladding solvent layer with a receiving groove121. The first cladding solvent layer is a layer of the first cladding layer forming solvent. In this embodiment, the first pressing roller211is rotated clockwise, and the first auxiliary roller212is rotated counterclockwise.

The first drying element218is used for solidifying the first cladding solvent layer to obtain a first cladding layer120.

The second roller pressing device260is used for filling a core layer forming solvent in the receiving groove121. The core layer forming solvent is a solvent for forming the core layer130. The second roller pressing device260is slightly different from the first roller pressing device210, and includes a second pressing roller261, a second auxiliary roller262, a second feeder263, and a second drying element268. The second auxiliary roller262has a smooth rolling surface262a. The difference between the second roller pressing device260and the first roller pressing device210is that the second pressing roller261has a smooth rolling surface261a.

The third roller pressing device290forms a second cladding layer140on the core layer130. The third roller pressing device290is slightly different from the first roller pressing device210, and includes a third pressing roller291, a third auxiliary roller292, a third feeder293, and a third drying element298. The third auxiliary roller292has a smooth rolling surface292a. The difference between the third roller pressing device290and the first roller pressing device210is that the third pressing roller291has a smooth rolling surface291a.

The direction of movement of the substrate110is substantially along its length. The distance between the first pressing roller211and the second pressing roller261, and the distance between the second pressing roller261and the third pressing roller291are less than the length of the substrate110. The first auxiliary roller212, the second auxiliary roller262, and the third auxiliary roller292are at a same height, therefore the substrate110can move from the first pressing device210to the second pressing device260, then automatically enter the third pressing device290. In this embodiment, the distance between the first pressing roller211and second pressing roller261is substantially equal to the distance between the second pressing roller261and the third pressing roller291.

Referring toFIG. 6, a method for manufacturing the OPCB100using the apparatus200includes the following steps.

In step 1, the substrate110is provided and is cleaned.

In step 2, the first cladding layer120is formed on the substrate110using the first roller pressing device210, the first cladding layer120defines the receiving groove121.

In step 3, the receiving groove121is filled with the core layer forming solvent using the second pressing roller260, the core layer130is thus obtained.

In step 4, a second cladding layer290is formed on the core layer130using the third roller pressing device290, thus the OPCB100is obtained.

Referring toFIGS. 7&8, an OPCB400of a second exemplary embodiment is slightly different from the OPCB100. The OPCB400includes a substrate410, a first cladding layer420, a core layer430, and a second cladding layer440. The first cladding layer420defines a receiving groove421that is substantially the same as the receiving groove121. The receiving groove421has a first inclined surface424and a second inclined surface425. The difference between the OPCB400and the OPCB100is that the shape of the core layer430is different from the shape of the core layer130, and the shape of the second cladding layer440is different from the shape of the second cladding layer140.

The second cladding layer440defines a first channel441and a second channel442communicating with the receiving groove421. The first channel441and the second channel442are substantially cuboid, and extend through the second cladding layer440. The orthogonal projection of the first inclined surface424on the first cladding layer420is superposed on the first channel441, and the orthogonal projection of the second inclined surface425on the first cladding layer420is superposed on the second channel442. The receiving groove421, the first channel441, and the second channel442are filled with the core layer430. That is, the core layer430includes a base431and two second protrusions432perpendicularly extending from the base431. The base431is received in the receiving groove421, and each second protrusion432is received in a respective one of the first channel441and the second channel442.

Referring toFIGS. 9 and 10, an apparatus600for manufacturing the OPCB400includes a first roller pressing device610, a second roller pressing device660, and a third roller pressing device690. The structure of the first roller pressing device610is substantially the same as the structure of the first roller pressing device210. The first roller pressing device610includes a first pressing roller611, a first auxiliary roller612, a first feeder613, and a first drying element618. The second roller pressing device660includes a second pressing roller661, a second auxiliary roller662, a second feeder663, and a second drying element668. The difference between the second roller pressing device661and the second roller pressing device260is that, the second rolling surface661aof the second pressing roller661defines a second impression pattern620different from the first impression pattern220. The second impression pattern620includes a plane surface621and two parallel straight grooves622. The two straight grooves622are defined in the plane surface621. The structure of the third roller pressing device690is substantially the same as the structure of the third roller pressing device290. The third roller pressing device690includes a third pressing roller691, a third auxiliary roller692, a third feeder693, and a third drying element698.

Referring toFIG. 11, a method for manufacturing the OPCB400ofFIG. 8using the apparatus600includes the following steps.

In step 1, the substrate410is provided and is cleaned.

In step 2, the first cladding layer420is formed on the substrate410using the first roller pressing device610, and the first cladding layer420defines the receiving groove421.

In step 3, the receiving grooves421are filled with the core layer forming solvent using the second roller pressing device660to form the base431and the two second protrusions432perpendicular to the base431, and the core layer430is thus formed.

In step 4, the second cladding layer440is formed on the core layer430using the third roller pressing device690, and the second cladding layer440defines two straight grooves622for receiving the two protrusions432, and the OPCB400is thus obtained.

The OPCB can be manufactured using the first to third roller pressing devices, and does not need manual mounting and demounting, therefore, the manufacturing efficiency is greatly improved.