Pyroelectric Optical Element Prevents Foreign Matter Adhesion
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing image capture apparatuses face challenges in preventing foreign matter from adhering to optical elements and solid-state image sensors due to electrostatic charges, which can lead to adverse optical effects and increased power consumption.
Innovation Solution
The apparatus features conductive shutter blades and optical elements with grounded surfaces, ensuring that the electrical potential of the shutter blades and optical elements is the same as the ground potential, preventing electrostatic attraction of foreign matter.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If a charged member is disposed around an optical element to prevent foreign matter adhesion, then foreign matter adhesion is prevented, but electric consumption increases and camera size cannot be reduced
Solution Approach 1:
The optical element utilizes its own pyroelectric properties to generate electric charges that prevent foreign matter adhesion, eliminating the need for external powered charged members. The optical element serves itself by converting temperature changes into electrical charges through its pyroelectric crystal structure, achieving foreign matter prevention without additional energy consumption.
Solution Approach 2:
The patent exploits the temperature-dependent electrical charge generation property of pyroelectric materials. By allowing temperature fluctuations in the optical element, electrical charges are generated dynamically in response to temperature changes, creating an electric field that repels charged foreign matter without requiring external power sources.
2Object-affected harmful factors
If conductive fine particles are dispersed in a reflection reducing film to prevent electrification, then foreign matter adhesion is prevented, but transmission factor decreases and light scattering occurs
Solution Approach 1:
Instead of using conductive particles that interfere with light transmission, the patent changes the material parameter to use pyroelectric crystal materials that generate electrical charges through temperature changes. This approach maintains optical transparency while achieving electrostatic repulsion of foreign matter, avoiding the light scattering and transmission loss problems associated with conductive particle dispersion.
Solution Approach 2:
The patent replaces the mechanical approach of dispersing conductive particles in a film with a field-based approach using pyroelectric charge generation. By substituting the particle-based electrical conduction method with a temperature-driven charge generation mechanism, the solution maintains optical clarity while achieving the desired electrostatic protection.
3Object-affected harmful factors
If the optical element is charged with electricity to create an electric field, then foreign matter adhesion is prevented, but the optical element requires additional components and space
Solution Approach 1:
The optical element performs multiple functions simultaneously: its primary optical function of filtering or modifying light and its secondary function of generating electrical charges through pyroelectric effects. By making the optical element itself the source of electrostatic protection, the patent eliminates the need for separate charged member components, reducing device complexity and camera size.
Solution Approach 2:
The patent merges the optical element with the electrostatic protection function by utilizing the pyroelectric properties of the optical element's crystal material. Instead of having separate components for optical processing and charge generation, the solution combines these functions into a single integrated optical element that both modifies light and generates repulsive electrical charges.
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 configuration effectively reduces the adhesion of foreign matter to optical elements and sensors, minimizing optical interference while maintaining energy efficiency and compact camera design.
Implementation Method 1
Crystal and lithium niobate used as a low-pass filter of the optical element are materials with pyroelectricity. Pyroelectricity is the electrical potential created in a particular crystal, in which when the crystal is polarized as a result of a change in temperature, or when a piezoelectric effect occurs due to deformation by temperature changes, the crystal material is charged with electricity.
Implementation Method 2
Pyroelectricity is the electrical potential created in a particular crystal, in which when the crystal is polarized as a result of a change in temperature, or when a piezoelectric effect occurs due to deformation by temperature changes, the crystal material is charged with electricity.
Data Source
AI summary
In an image capture apparatus, the surface of an optical element and a shutter are made to have conductivity, and they are grounded so as to have the same potential, so that adhesion of foreign matter onto the surface of the optical element can be prevented.