Stacked Substrate Solid-State Imaging Device for Signal Crosstalk Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional solid-state imaging devices that aim to capture both imaging signals and light field signals often compromise on signal quality, as they use the same pixels for both purposes, leading to a trade-off in signal-to-noise ratio (S/N ratio) and increased crosstalk.
Innovation Solution
A solid-state imaging device with multiple substrates, where one substrate handles imaging signals and another handles light field signals, utilizing micro lenses and light pipes to selectively direct light and transfer charges between substrates, allowing for separate and efficient reading of imaging and light field signals without compromising the S/N ratio.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If the same pixels are used for both imaging signals and light field signals, then the device complexity is reduced, but the signal-to-noise ratio deteriorates and crosstalk increases
Solution Approach 1:
The imaging device is divided into two separate substrates: a first substrate containing photoelectric conversion units for imaging signals, and a second substrate containing photoelectric conversion units for light field signals. This segmentation allows each substrate to be optimized for its specific function, preventing signal interference and maintaining high signal-to-noise ratios for both imaging and light field capture simultaneously
Solution Approach 2:
The invention transitions from a single-plane pixel array to a three-dimensional stacked substrate architecture. By arranging photoelectric conversion units for different signal types on separate substrates in the vertical dimension, the system eliminates lateral crosstalk while maintaining compact form factor, thus improving signal quality without substantially increasing device complexity
2Reliability
If separate substrates are used for imaging and light field signals, then the signal-to-noise ratio is improved, but the device complexity increases
Solution Approach 1:
The invention merges the imaging function and light field capture function into a single integrated stacked substrate device. The first substrate with imaging photoelectric conversion units and the second substrate with light field photoelectric conversion units are vertically integrated and processed together as one device unit, allowing simultaneous acquisition of both signal types without requiring separate devices, thus managing complexity through integration rather than multiplication
3Device complexity
If the same pixels are used for both purposes, then the photoelectric conversion unit size is constrained, but the device complexity is reduced
Solution Approach 1:
By segmenting the photoelectric conversion units onto separate substrates dedicated to imaging and light field functions, each substrate can accommodate larger photoelectric conversion units without compromise. The first substrate's photoelectric conversion units can be optimized for imaging with sufficient area, while the second substrate's units are optimized for light field capture, eliminating the size constraints imposed by shared pixel usage
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 the acquisition of high-quality imaging and light field signals simultaneously, maintaining a sufficient signal-to-noise ratio and reducing crosstalk, while allowing for larger photoelectric conversion units and enhanced signal processing capabilities.
Implementation Method 1
a micro lens that is provided on the first substrate and condenses light incident on the first photoelectric conversion units; and a light pipe that is provided at the first substrate and guides the light condensed by the micro lens to a region of the second substrate
Implementation Method 2
a first substrate that has a plurality of first photoelectric conversion units arranged in two dimensions; a second substrate that has a plurality of second photoelectric conversion units arranged in two dimensions
Data Source
AI summary
A first substrate has a plurality of photoelectric conversion units arranged in two dimensions. A second substrate has a plurality of photoelectric conversion units arranged in two dimensions. A plurality of photoelectric conversion units are arranged in a region of the second substrate corresponding to a region of the first substrate where one photoelectric conversion unit is arranged. The imaging signals based on signal charges stored in the photoelectric conversion units and the light field signals based on signal charges stored in the photoelectric conversion units are read.