Electrochromic ND Filter Transmittance Correction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Image quality is compromised due to optical density unevenness caused by potential distribution in electrochromic ND filters used in image capturing apparatuses, leading to brightness inconsistencies in captured images.
Innovation Solution
An image capturing apparatus equipped with processors that acquire and correct image signals based on the distribution characteristics of the electrochromic element's transmittance, using current values and temperature data to adjust image processing and correct for transmittance unevenness.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the film thickness of the transparent electrode is increased to lower resistance, then the voltage drop is reduced, but the light transmittance decreases
Solution Approach 1:
The patent changes the material composition parameters of the transparent electrode by incorporating a metal oxide layer (such as indium oxide, tin oxide, or fluorine-doped tin oxide) with specific optical properties. This allows optimization of both electrical conductivity and optical transmittance by adjusting the material composition rather than simply increasing thickness
Solution Approach 2:
The transparent electrode is constructed as a composite structure combining a resin layer and a metal oxide layer. The resin layer provides mechanical support and basic transparency, while the metal oxide layer provides enhanced electrical conductivity and controlled optical properties, achieving both low resistance and high transmittance simultaneously
2Adaptability or versatility
If current is increased to change transmittance of the electrochromic element, then the light amount control is improved, but potential distribution and optical density unevenness occur
Solution Approach 1:
The patent replaces the mechanical ND filter system with an electrochromic element that uses electrical current to control transmittance. This substitution allows continuous and precise control of light amount without mechanical movement, eliminating disturbances to the image sensor while achieving uniform transmittance changes across the element surface
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
The solution effectively suppresses image quality degradation by correcting for transmittance unevenness, ensuring consistent brightness and improved image quality even under varying light conditions.
Implementation Method 1
an optical member using an electrochromic element (EC element) that is capable of electrically controlling a transmittance of light
Implementation Method 2
a relatively large current flows to the EC element, a potential distribution is generated in the plane of the EC element due to a voltage drop
Data Source
AI summary
An image capturing apparatus is provided. The image capturing apparatus comprises an image capturing element configured to capture an object image formed by light that has passed through an optical member using an electrochromic element and capable of electrically controlling a transmittance of the light. The image capturing apparatus further comprises one or more processors that execute a program stored in a memory, wherein the program, when executed by the one or more processors, causes the one or more processors to function as: a distribution acquisition unit configured to acquire a distribution characteristic of a transmittance of the electrochromic element based on a current value flowing to the electrochromic element; and an image processing unit configured to correct an image signal captured by the image capturing element in accordance with the distribution characteristic.