Optoelectronic modules with temperature-independent characteristics

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Solution Overview

Problem

Optoelectronic modules with temperature-dependent performance characteristics pose challenges in collecting proximity data accurately over a range of operating temperatures, as variations in temperature affect the intensity of signals collected by light-sensitive and light-generating components, obscuring proximity data variations.

Innovation Solution

The development of discrete optoelectronic modules with substantially temperature-independent performance characteristics, achieved through the configuration of light-generating and light-sensitive components, including VCSELs and photodiodes, with complementary temperature-dependent performance characteristics, and the use of dielectric materials or active feedback loops to compensate for temperature changes, ensuring data invariance across a temperature range of -5 to 45°C without increasing manufacturing costs or module size.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If conventional optoelectronic modules are used, then the module can collect proximity data, but the performance characteristics are temperature-dependent causing signal intensity variations that obscure proximity data

Engineering Contradiction:
Improveproximity data accuracyVSAvoidtemperature-dependent performance variation
Core Design Contradiction:
Measurement precisionVSTemperature

Solution Approach 1:

The patent applies parameter changes by selecting light-generating and light-sensitive components with specific temperature-dependent characteristics that complement each other. The light-generating component (VCSEL) exhibits a redshift in emission wavelength with temperature increase, while the light-sensitive component (photodiode) exhibits a blueshift in peak sensitivity wavelength. By carefully matching these wavelength shifts, the module maintains temperature-independent performance characteristics across the operating range of -5°C to 45°C, achieving signal variation of only 2% despite temperature changes.

Inventive Principle:
Principle #35Parameter changes

2Reliability

If temperature compensation approaches are implemented, then temperature-independent performance can be achieved, but the module complexity and manufacturing cost increase

Engineering Contradiction:
Improvetemperature-independent performanceVSAvoidmodule structure complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent converts the harmful temperature-dependent wavelength shifts into a beneficial complementary relationship. Instead of trying to eliminate or compensate for the temperature effects using additional components, the invention selects components whose temperature drift characteristics naturally complement each other. The VCSEL's redshift and photodiode's blueshift cancel out, transforming temperature sensitivity from a problem into a self-correcting feature, thereby achieving temperature-independent performance without adding complexity.

Inventive Principle:
Principle #22Blessing in disguise (Convert harm into benefit)

3Reliability

If temperature compensation approaches are implemented, then temperature-independent performance can be achieved, but manufacturing costs increase

Engineering Contradiction:
Improvetemperature-independent performanceVSAvoidmanufacturing cost
Core Design Contradiction:
ReliabilityVSEase of manufacture

Solution Approach 1:

The patent employs standard, commercially available VCSEL and photodiode components that can be manufactured using existing processes. By relying on the inherent complementary temperature characteristics of these standard components rather than requiring custom-designed or specially compensated components, the solution achieves temperature-independent performance at lower manufacturing cost. The approach avoids expensive temperature sensors, compensation circuits, or calibration procedures.

Inventive Principle:
Principle #27Cheap short-living objects (Disposable)

4Reliability

If temperature compensation approaches are implemented, then temperature-independent performance can be achieved, but the module form factor increases

Engineering Contradiction:
Improvetemperature-independent performanceVSAvoidmodule form factor
Core Design Contradiction:
ReliabilityVSVolume of moving object

Solution Approach 1:

The patent extracts and eliminates the need for temperature compensation components by utilizing the inherent complementary temperature characteristics of the light-generating and light-sensitive components. By removing temperature sensors, compensation circuits, and additional calibration mechanisms, the module maintains a compact form factor while achieving temperature-independent performance through the wavelength shift complementarity of the core optical components.

Inventive Principle:
Principle #2Taking out (Extraction)

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

These modules collect data that is substantially invariant to temperature changes, improving performance, reducing manufacturing costs, and maintaining accuracy across varying temperatures, which is advantageous in applications like smartphones and other host devices where proximity data is critical.

Implementation Method 1

VCSELs can exhibit a cavity mode and/or a gain-peak shift with increasing temperature. A 980-nm VCSEL with InGaAs quantum wells, for example, can be characterized by a cavity mode shift of 0.07 nm°C -1

Methodology Applied
Scientific EffectCavity mode shift:

Implementation Method 2

VCSELs can exhibit a cavity mode and/or a gain-peak shift with increasing temperature

Methodology Applied
Scientific EffectGain-peak shift:

Implementation Method 3

a light-sensitive component, such as a photodiode, operable to collect light emitted by the light source

Methodology Applied
Scientific EffectPhotoelectric effect: Photoelectric Effect

Implementation Method 4

the optoelectronic modules include one or more optical components configured to complement the temperature-dependent performance characteristics of the light-generating and/or light-sensitive components. In such implementations, the optical components include a dielectric material with a particular thickness such as a dielectric optical filter

Methodology Applied
Scientific EffectDielectric filtering: Filter (optical)

Data Source

PatentEP3652520B1Optoelectronic modules with temperature-independent characteristics
Publication Date: 2024.09.25 AMS OSRAM ASIA PACIFIC PTE LTD
  • EP3652520B1 patent drawingFigure 1A~1B

AI summary

The present disclosure is directed to optoelectronic modules with substantially temperature-independent performance characteristics and host devices into which such optoelectronic modules can be integrated. In some instances, an optoelectronic module can collect proximity data using light-generating components and light-sensitive components that exhibit temperature-dependent performance characteristics. The light-generating components and light-sensitive components can be configured such that they exhibit complementing temperature-dependent performance characteristics such that the operating performance of the optoelectronic module is substantially temperature independent.