Image Sensor Pixel Active Area Reduction for Noise Mitigation

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Conventional image sensors, such as CMOS and CCD sensors, suffer from high read noise and motion blur, especially under low light conditions, which degrades the quality of pass-through views in mixed-reality systems.

Innovation Solution

The implementation of image sensors with modified pixel designs that reduce dark shot noise, achieved by reducing the active area and active region depth of the image sensing pixels, thereby mitigating sensor noise.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Object-affected harmful factors

If the active area of image sensing pixels is reduced to mitigate dark shot noise, then sensor noise is reduced and low light imaging performance is improved, but the light collection area is reduced which may decrease signal strength

Engineering Contradiction:

Improvedark shot noiseVSAvoidlight collection area

Core Design Contradiction:

Object-affected harmful factorsVSQuantity of substance

Solution Approach 1:

The patent applies parameter changes by reducing the active area dimensions (length and width) of image sensing pixels to mitigate dark shot noise. By changing the geometric parameters of the active area, the invention reduces the noise floor while maintaining acceptable light collection through optimized pixel design and arrangement.

Inventive Principle:

Principle #35Parameter changes

2Device complexity

If conventional image sensors are used under low light conditions, then device simplicity is maintained, but read noise and motion blur degrade image quality

Engineering Contradiction:

Improvesensor design simplicityVSAvoidread noise and motion blur

Core Design Contradiction:

Device complexityVSObject-affected harmful factors

Solution Approach 1:

The patent applies local quality by modifying only the active area of the pixel while maintaining the overall pixel structure and readout circuitry. The isolation region and other components remain unchanged, allowing the invention to address noise issues locally without complicating the entire sensor design.

Inventive Principle:

Principle #3Local quality

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 approach results in noise-mitigated imagery with improved low light imaging performance, reducing dark shot noise and enhancing image quality, particularly in mixed-reality systems.

Implementation Method 1

each pixel is configured to generate electron-hole pairs in response to detected photons

Methodology Applied

Scientific EffectPhotoelectric Effect: Photoelectric Effect

Data Source

PatentUS12302016B2Image sensing pixel configurations for reduced sensor noise

Publication Date: 2025.05.13 MICROSOFT TECHNOLOGY LICENSING LLC

AI summary

An image sensor configured to capture imagery with mitigated noise includes a plurality of image sensing pixels arranged to form a sensor array. Each image sensing pixel of the plurality of image sensing pixels comprises an active area configured to receive photons to facilitate image capture. Each active area comprises a length and a width. For at least one image sensing pixel of the plurality of image sensing pixels, the length or the width of the active area is smaller than about 80% of a pixel pitch measurement between the at least one image sensing pixel and an adjacent image sensing pixel. A size of the active area relative to the pixel pitch measurement contributes to mitigating sensor noise for the image sensor.