Camera Flash Color Temperature Correction for Illumination Accuracy
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing camera systems face challenges in accurately determining the amount of light for main emission during photography due to differences in color temperature between preparatory and main emission lights, leading to inadequate illumination, especially for subjects far away, and increased battery consumption when trying to compensate for low light emission efficiency.
Innovation Solution
A camera system that includes a light emitting unit with variable color temperature, a calculator to determine the amount of light for main emission based on image capture signals, and a corrector to adjust for color temperature differences in light emission efficiency, sensitivity, and reflectivity, ensuring proper illumination while minimizing power consumption.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If the color temperature of preparatory emission light is matched to ambient light, then the comfort of the final image is improved, but the light emission efficiency decreases leading to insufficient illumination for far subjects
Solution Approach 1:
The patent changes the color temperature parameter of the preparatory emission light to be different from ambient light (e.g., higher color temperature) to achieve better light emission efficiency and sufficient illumination, while separately processing the color temperature of the final image to maintain viewer comfort. This decouples the two requirements by allowing different color temperatures at different stages.
2Illumination intensity
If the amount of light during preparatory emission is increased to compensate for low emission efficiency, then the illumination intensity is improved, but the battery power consumption increases
Solution Approach 1:
The patent changes the color temperature parameter of the preparatory light to optimize emission efficiency, which allows achieving sufficient illumination intensity without proportionally increasing the light amount. This parameter optimization reduces the energy required for preparatory emission while maintaining adequate illumination for accurate exposure calculation.
3Power
If the color temperature of preparatory emission light is different from main emission light, then the light emission efficiency is improved, but the measurement precision of reflected light amount decreases
Solution Approach 1:
The patent uses feedback by measuring the reflected light amount during preparatory emission and then calculating the required main emission light amount while correcting for the color temperature difference. The system incorporates correction coefficients that account for the wavelength dependence of reflectivity and sensor sensitivity, allowing accurate main emission determination despite the color temperature change.
Solution Approach 2:
The patent systematically changes the color temperature parameter between preparatory and main emission, and compensates for this change through calculated correction coefficients. These coefficients adjust for the effects of different color temperatures on reflectivity measurement and sensor response, maintaining measurement precision while benefiting from improved emission efficiency.
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 system provides accurate illumination for both near and far subjects by correcting for color temperature differences, ensuring adequate light emission while optimizing battery usage by matching preparatory and main emission light efficiencies.
Implementation Method 1
an imaging element that captures an image of the photographic subject and outputs an image capture signal
Implementation Method 2
a light emitting unit that performs a main emission of light in which during photography a photographic subject is illuminated with a first light having a first color temperature
Data Source
AI summary
A camera system includes: a light emitting unit that performs a main emission of light in which during photography a photographic subject is illuminated with a first light having a first color temperature, and a preparatory emission of light in which the photographic subject is illuminated with a second light having a second color temperature before photography; an imaging element that outputs an image capture signal; a calculator that calculates an amount of the first light by the light emitting unit, based upon the image capture signal output during the preparatory emission of light; a corrector that corrects the calculated amount of the first light, based upon a color temperature difference between the first color temperature and the second color temperature; and a controller that controls the light emitting unit to perform the main emission of light at the amount of the first light after correction by the corrector.