Optical Waveguide Alignment Using Fluorescent Light Observation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current optical axis alignment methods for waveguides in optical communications face challenges such as precision issues due to small differences in refractive indices between core and clad, leading to significant transmission loss from slight misalignments, and existing techniques either compromise on precision or increase propagation loss by adding fluorescent materials.
Innovation Solution
An aligner system that uses an excitation light launching section to cause the waveguide to emit fluorescent light, a light observing section to monitor this light from a side face, and a connection adjusting section to optimize the optical connection based on intensity, allowing for precise alignment without additional propagation loss.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a launching optical fiber is abutted against one end face and emission light monitoring optical fiber is abutted against the other end face for simultaneous position adjustment, then the alignment process can be completed, but the optical fibers and waveguide may be adjusted to local optimum positions reducing precision
Solution Approach 1:
The patent divides the alignment process into two independent stages: first adjusting the incidence side optical fiber position based on fluorescent light intensity from the core, then separately adjusting the outgoing side optical fiber position. This segmentation prevents the simultaneous adjustment problem that leads to local optimum positions, allowing each side to be optimized independently for maximum alignment precision.
2Ease of operation
If a substance producing fluorescent light is added to the core material and ultraviolet rays are irradiated from the side face, then the optical fibers on incidence side and outgoing side can be separately adjusted, but a dedicated fluorescent light device is required and optical axis alignment precision may be low
Solution Approach 1:
The patent makes the optical fiber serving as the light launching medium also serve as the light source for fluorescence excitation. By launching ultraviolet light through the same optical fiber that will be aligned to the waveguide core, the system eliminates the need for separate fluorescent light devices while maintaining the ability to separately adjust both optical fibers. This multi-functionality approach preserves alignment precision by using the actual communication optical fiber for excitation.
3Difficulty of detecting and measuring
If coloring matter or fluorescent material is added to the waveguide core material, then the core position can be made visible or fluorescent light can be emitted, but the propagation loss of light in optical communications increases
Solution Approach 1:
The patent extracts the fluorescent material addition step from the waveguide core material composition. Instead of permanently adding fluorescent dye to the waveguide core (which would cause propagation loss), the system uses the optical fiber itself as the excitation source, launching ultraviolet light through the fiber to excite fluorescent material only at the core location during alignment. This temporary, localized excitation approach eliminates the need for permanent fluorescent material incorporation while maintaining core visibility during alignment.
4Productivity
If the wavelength of light is chosen for optical communications, then high-rate transmission is achieved, but the light cannot be externally observed due to being outside visible region and not being absorbed by transmitting material
Solution Approach 1:
The patent applies local quality by using different wavelengths for different functions: the waveguide core transmits communication light at wavelengths optimized for high-rate transmission (1.55, 1.3, or 0.85 microns), while the alignment process uses ultraviolet light excitation to generate visible fluorescent light only at the core location for observation. This allows the communication function to operate at optimal wavelengths while the alignment function uses visible light for external observation, with each wavelength optimized for its specific purpose.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This method enhances the precision of optical axis alignment, preventing local optimum positions and reducing propagation loss, thereby improving the efficiency of optical interconnections in communications.
Implementation Method 1
an excitation light launching section that launches light that causes the waveguide to emit fluorescent light into the waveguide
Implementation Method 2
a light observing section that observes the waveguide from a side face, which is different from the end face from which light is launched into the waveguide or light having propagated through the waveguide is emitted, and receives the fluorescent light emitted by the waveguide
Implementation Method 3
Optical fibers and waveguides, which transmit light using the total internal reflection at the interface between the core and the clad whose indexes of refraction are different
Data Source
AI summary
Apparatus and method which adjusts an optical connection between a waveguide and an optical interconnection component that launches light into the waveguide or receives light emitted from the waveguide. The apparatus includes: an excitation light element emitting light that causes the waveguide to fluoresce into the waveguide via the optical interconnection component; an observation unit that observes the waveguide from a side face, different from the end face into which light is launched into the waveguide or light having propagated through the waveguide is emitted, and which receives fluorescent light emitted by the waveguide; and a connection adjusting component that adjusts the optical connection between the optical interconnection component and the waveguide based on the intensity of the fluorescent light received at the light observing section.