Endoscope Imaging Device Narrow Band Light Pixel Saturation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing endoscope systems face challenges in capturing high-resolution images of capillary vessels and mucosal microscopic patterns using narrow band light, as the blue filter pixels tend to saturate due to high sensitivity, leading to degraded image resolution and insufficient signal-to-noise ratio.
Innovation Solution
The imaging device employs a color filter with specific spectral characteristics for red, green, and blue filters, and a control unit that adjusts the accumulation time of blue filter pixels to prevent saturation, allowing for higher intensity narrow band light emission and improved signal quality, while maintaining high color reproducibility even with white light illumination.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If narrow band light irradiation is used to highlight capillary vessels and mucosal patterns, then image contrast and detail are improved, but blue filter pixels saturate due to high sensitivity, degrading image resolution
Solution Approach 1:
The patent applies different accumulation times to different color filter pixels based on their spectral sensitivity characteristics. Blue filter pixels, which have high sensitivity to narrow band light, are assigned shorter accumulation times to prevent saturation, while red and green filter pixels use longer accumulation times to maintain signal strength. This localized differentiation of exposure parameters resolves the contradiction between contrast enhancement and resolution maintenance.
Solution Approach 2:
The patent dynamically adjusts the accumulation time parameter for blue filter pixels specifically, setting it to a shorter duration compared to red and green filter pixels. This parameter change prevents blue pixel saturation while maintaining adequate signal levels in other color channels, thereby preserving both image contrast and resolution when using narrow band light illumination.
2Measurement precision
If higher intensity narrow band light is emitted to improve signal-to-noise ratio, then signal quality is improved, but blue filter pixels saturate more easily
Solution Approach 1:
The patent implements differential accumulation time control where blue filter pixels receive shorter exposure durations specifically tailored to their high sensitivity characteristics. This allows the system to emit higher intensity narrow band light for improved signal-to-noise ratio without causing blue pixel saturation, as the reduced accumulation time compensates for the increased light intensity in the blue channel.
Solution Approach 2:
The patent preemptively reduces the accumulation time for blue filter pixels before saturation can occur. By anticipating the high sensitivity of blue pixels to narrow band light, the system pre-adjusts the exposure parameter to prevent saturation, enabling higher intensity illumination to be used safely for improved signal quality.
3Measurement precision
If blue filter pixels use longer accumulation time to maintain signal strength, then signal-to-noise ratio is improved, but pixel saturation occurs with narrow band light
Solution Approach 1:
The patent changes the accumulation time parameter specifically for blue filter pixels, setting it to a shorter value that prevents saturation under narrow band light illumination. This parameter adjustment maintains adequate signal-to-noise ratio by balancing the reduced exposure time with the high sensitivity of blue pixels to the illumination spectrum, avoiding the saturation that would occur with equal accumulation times across all color channels.
4Measurement precision
If color filters are designed with standard spectral characteristics, then color reproducibility with white light is achieved, but sensitivity to narrow band light causes saturation
Solution Approach 1:
The patent maintains standard color filter spectral characteristics for accurate color reproduction with white light, but compensates for the high blue sensitivity under narrow band light by applying differential accumulation time control. Blue filter pixels use shorter exposure times specifically when narrow band light is detected or used, allowing the system to preserve both color accuracy with white light and saturation prevention with narrow band light.
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 enables high-resolution image capture with either narrow band light or white light, preventing pixel saturation and ensuring high color reproducibility, thus overcoming the limitations of previous systems.
Implementation Method 1
a blue filter having spectral characteristics where a maximum value of its transmission spectrum is in the blue wavelength band and transmittance of the wavelength band of a narrow band light is higher than the transmission spectrum in the red and green wavelength bands
Implementation Method 2
a red filter having spectral characteristics where a maximum value of its transmission spectrum is in the red wavelength band and a minimum value of its transmission spectrum is near the maximum value of the transmission spectrum of the blue wavelength band, and a green filter having spectral characteristics where a maximum value of its transmission spectrum is in the green wavelength band and a minimum value of its transmission spectrum is near the maximum value of the transmission spectrum of the blue wavelength band
Implementation Method 3
an imaging element having a color filter provided on a light receiving surface thereof, the color filter having three types of filters arranged in a predetermined pattern, the three types of filters respectively transmitting red (R), green (G), and blue (B)
Data Source
AI summary
An imaging device includes: plural pixels; a color filter including a blue filter having spectral characteristics where a maximum value of its transmission spectrum is in the blue wavelength band and transmittance of the wavelength band of a narrow band light is higher than the transmission spectrum in the red and green wavelength bands, a red and green filters having spectral characteristics where minimum values of their transmission spectra are near the maximum value of the transmission spectrum of the blue wavelength band, and having spectral characteristics where their transmission spectra gradually increase toward a short wavelength side from 440 nm; and a control unit configured to execute control of making an accumulation time of a pixel of the plural pixels shorter than accumulation times of pixels having other filters arranged thereon, the pixel having highest spectral sensitivity to the narrow band light.