Unlock instant, AI-driven research and patent intelligence for your innovation.

Spot size converter

a converter and size technology, applied in the field of spot size converters, can solve the problems of large polarization dependency and many of them are extremely difficult to manufacture, and achieve the effect of easy manufacturing structure and no polarization dependency

Inactive Publication Date: 2010-03-04
OKI ELECTRIC IND CO LTD
View PDF5 Cites 3 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Benefits of technology

The solution achieves efficient coupling with external optical devices while minimizing polarization dependency and manufacturing complexity, with high coupling efficiency and ease of production using semiconductor fabrication methods.

Problems solved by technology

One problem with these known spot size converters is their large polarization dependency.
Another problem is that many of them are extremely difficult to manufacture.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Spot size converter
  • Spot size converter
  • Spot size converter

Examples

Experimental program
Comparison scheme
Effect test

first embodiment

[0041]Referring to FIG. 1, the spot size converter 10 in the first embodiment includes a substrate 12, a clad 14, and a first core 18 having an optical input-output region 16 and a main core region 17.

[0042]The substrate 12 is preferably a flat rectangular solid body of, for example, monocrystalline silicon with parallel major surfaces.

[0043]The clad 14 is formed on the entire upper major surface 12a of the substrate 12. The material of the clad 14 is preferably silicon dioxide (SiO2). The first core 18 extends straight through the clad 14, paralleling the upper major surface 12a of the substrate 12.

[0044]Light propagates in the direction in which the first core 18 extends, which will be referred to as the length direction. The direction parallel to the upper major surface 12a of the substrate 12 and orthogonal to the length direction will be referred to as the width direction. The direction orthogonal to the upper major surface 12a of the substrate 12 will be referred to as the thi...

second embodiment

[0109]Next, a spot size converter 30 according to a second embodiment of the invention will be described with reference to FIGS. 15 to 23.

[0110]Referring to FIG. 15, the spot size converter 30 has the same structure as the spot size converter 10 in the first embodiment except that the projecting ramp surrounding the optical input-output region 16 is turned on its side. As a result, a line normal to the sloping surface 34a of the first core 34 lies in a plane parallel to the upper major surface 12a of the substrate 12, whereas in the first embodiment a line normal to the sloping surface 18a of the first core 18 was disposed in a plane orthogonal to the upper major surface 12a of the substrate 12, as can be appreciated from FIGS. 1 to 3.

[0111]The alignment of the four sides 341, 342, 343, 344, of the first core 34 of the spot size converter 30, shown in FIG. 16, differs from the alignment of the four sides 181, 182, 183, 184, of the first core 18 of the spot size converter 10 shown in...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

PropertyMeasurementUnit
refractive indexaaaaaaaaaa
sizeaaaaaaaaaa
thicknessaaaaaaaaaa
Login to View More

Abstract

A spot size converter has a first core, a larger second core, and a clad disposed on a substrate. The first core has a rectilinear cross-sectional shape and is embedded in the clad, except at its ends. One of these ends has a sloping surface along which the thickness of the first core tapers gradually to zero. The second core, which has a refractive index intermediate between the refractive indexes of the first core and clad, sits on the clad and covers the sloping end surface of the first core. Light propagates through the first core, then through the second core into an external optical device, or propagates from an external optical device through the second core into the first core. This arrangement provides a spot size converter having an easily manufacturable structure and no polarization dependency.

Description

BACKGROUND OF THE INVENTION[0001]1. Field of the Invention[0002]The present invention relates to a spot size converter used as an optical link between a silicon-wire waveguide and an external optical device such as an optical fiber or laser diode.[0003]2. Description of the Related Art[0004]Silicon-based waveguide technology has been attracting attention recently. A silicon-wire waveguide, in which a silicon (Si) core is surrounded by a silicon dioxide (SiO2) clad having a much smaller refractive index, is one type of silicon-based waveguide. Because of the large difference between the refractive indexes of the core and clad, light is strongly confined in the core. This tight confinement enables a silicon-wire waveguide to turn corners with a radius of curvature as small as about one micrometer (1 μm). Silicon-wire waveguides can accordingly be used to create optical devices with submicron-order dimensions, which can be integrated with electronic devices on the same silicon chip.[00...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Applications(United States)
IPC IPC(8): G02B6/26B44C1/22
CPCG02B6/1228
Inventor OKAYAMA, HIDEAKI
Owner OKI ELECTRIC IND CO LTD