Infrared Component Equalization in Image Pickup Apparatus

Solution Overview

Problem

Digital image pickup devices suffer from deteriorated color reproducibility due to infrared light contamination in incoming light, and existing infrared light cut filters are costly, difficult to implement, and often attenuate visible light, leading to reduced sensitivity.

Innovation Solution

An image pickup apparatus with a color filter that transmits infrared light and a control unit that switches between addition and subtraction processing to correct infrared components in the output signal, ensuring equal infrared light components across color channels without the need for an infrared light cut filter.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If an infrared light cut filter is used to remove infrared light, then color reproducibility is improved, but cost increases and device complexity increases

Engineering Contradiction:

Improvecolor reproducibilityVSAvoidoptical system complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent replaces the mechanical/optical infrared light cut filter with a signal processing approach. The image pickup device captures both visible light and infrared light components, and the control unit processes the signals by subtracting the infrared component from the visible light component, thereby eliminating the need for physical infrared filtering mechanisms.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent introduces an intermediary signal processing step between the image pickup device and the output. The control unit acts as an intermediary that receives the raw signal containing both visible and infrared components, processes them by separating and equalizing the infrared components across color channels, and produces the final corrected output signal.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Reliability

If an infrared light cut filter is used to remove infrared light, then color reproducibility is improved, but visible light sensitivity deteriorates

Engineering Contradiction:

Improvecolor reproducibilityVSAvoidvisible light sensitivity

Core Design Contradiction:

ReliabilityVSIllumination intensity

Solution Approach 1:

The patent replaces the mechanical/optical infrared light cut filter with a signal processing approach. The image pickup device captures both visible light and infrared light components, and the control unit processes the signals by subtracting the infrared component from the visible light component, thereby eliminating the need for physical infrared filtering mechanisms.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent converts the harmful infrared light contamination into a useful signal for correction. Instead of simply blocking infrared light, the system captures the infrared component and uses it to create a correction signal that is then applied to remove the infrared contamination from the visible light signal, thereby turning the harmful factor into a beneficial correction mechanism.

Inventive Principle:

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

3Reliability

If an infrared light cut filter is used to remove infrared light, then color reproducibility is improved, but manufacturing cost increases

Engineering Contradiction:

Improvecolor reproducibilityVSAvoidmanufacturing cost

Core Design Contradiction:

ReliabilityVSEase of manufacture

Solution Approach 1:

The patent replaces the mechanical/optical infrared light cut filter with a signal processing approach. The image pickup device captures both visible light and infrared light components, and the control unit processes the signals by subtracting the infrared component from the visible light component, thereby eliminating the need for physical infrared filtering mechanisms.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent replaces the expensive, complex infrared light cut filter with a simpler, more economical signal processing system. The correction is achieved through computational methods using the image pickup device's existing sensors and processing capabilities, significantly reducing manufacturing costs while maintaining color reproducibility.

Inventive Principle:

Principle #27Cheap short-living objects (Disposable)

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

Enhances color reproducibility and sensitivity by adjusting infrared light components, suppressing noise, and maintaining accurate white balance without degrading image quality or requiring expensive filters.

Implementation Method 1

a color filter of multiple colors which transmits an infrared light component

Methodology Applied

Scientific EffectInfrared light transmission: Infrared Radiation

Implementation Method 2

an image pickup device which receives an incident light by way of the color filter

Methodology Applied

Scientific EffectPhotoelectric conversion: Photoelectric Effect

Data Source

PatentUS7773136B2Image pickup apparatus and image pickup method for equalizing infrared components in each color component signal

Publication Date: 2010.08.10 SEMICON COMPONENTS IND LLC

AI summary

An image pickup device receives an incident light by way of the color filter that also transmits an infrared light component. For the purpose of correcting an infrared light component contained in an output signal, a control unit adds correcting infrared light components to image signals of multiple colors supplied from the image pickup device, respectively. To remove the infrared light components contained in the output signals, the correcting infrared light components are subtracted from the image signals of multiple colors supplied from the image pickup device. The control unit switches between an addition processing where an infrared light component is added and a subtraction processing where the infrared component is subtracted, according to a predetermined condition.