Dynamic Vision Sensor Imaging Device With Stacked Chip Architecture
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Non-scanning type imaging devices, such as DVS, are limited to detecting event occurrences based on luminance changes and cannot output signals at gradation levels corresponding to incident light amounts.
Innovation Solution
The imaging device employs a stacked chip structure with a first-layer semiconductor chip containing a pixel array unit that mixes event pixels for detecting luminance changes and gradation pixels for outputting signals at gradation levels. A second-layer semiconductor chip provides analog front-end units for processing event and gradation pixel signals.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a non-scanning type imaging device uses only event pixels to detect luminance changes, then motion detection capability is improved, but the ability to output gradation level signals according to incident light amount deteriorates
Solution Approach 1:
The imaging device divides the pixel array into two distinct types: event pixels for motion detection and gradation pixels for capturing absolute luminance information. This segmentation allows each pixel type to be optimized for its specific function while working together to provide comprehensive imaging capability
Solution Approach 2:
The imaging device achieves multi-functionality by integrating both event pixel and gradation pixel capabilities within a single device. The event pixels provide motion detection functionality while gradation pixels provide absolute luminance measurement, allowing the device to output both event detection signals and gradation level signals
2Adaptability or versatility
If a stacked chip structure is used to integrate multiple pixel types and processing units, then functional versatility is improved, but device complexity increases
Solution Approach 1:
The device transitions from a planar single-chip structure to a three-dimensional stacked chip architecture. By stacking multiple semiconductor chips vertically, the device integrates event pixels, gradation pixels, and their respective processing units in different layers, reducing lateral complexity while increasing vertical functionality
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 allows the imaging device to output both event detection signals and pixel signals at gradation levels, enhancing its capability to detect motion and capture images without motion blur, while also improving signal-to-noise ratio in gradation data.
Implementation Method 1
a pixel array unit in which an event pixel that detects a phenomenon in which an amount of change in luminance of a pixel, which photoelectrically converts incident light
Implementation Method 2
a distance measurement pixel including a light-receiving element that receives, from a target of distance measurement, reflected light based on irradiation light from a light source unit and generates a signal in response to reception of a photon
Data Source
AI summary
The present disclosure provides an imaging device capable of outputting a signal other than an event detection signal, such as a pixel signal at a gradation level. The imaging device has a stacked chip structure formed by stacking at least two semiconductor chips including a first-layer semiconductor chip and a second-layer semiconductor chip. The first-layer semiconductor chip has a pixel array unit in which an event pixel that outputs an event detection signal, and a distance measurement pixel are mixed. The second-layer semiconductor chip is provided with an analog front-end unit for an event pixel that processes the event detection signal and with an analog front-end unit for a distance measurement pixel that processes the signal from the light-receiving element, corresponding to each of the event pixel and the distance measurement pixel.