Image sensor incuding CMOS image sensor pixel and dynamic vision sensor pixel
An image sensor includes a CIS (CMOS image sensor) pixel, a DVS (dynamic vision sensor) pixel, and an image signal processor. The CIS pixel includes a photoelectric conversion device generating charges corresponding to an incident light and a readout circuit generating an output voltage corresponding to the generated charges. The DVS pixel detects a change in an intensity of the incident light based on the generated charges to output an event signal and does not include a separate photoelectric conversion device. The image signal processor allows the photoelectric conversion device to be connected to the readout circuit or the DVS pixel.
1. An image sensor comprising:
a complementary metal-oxide semiconductor image sensor (CIS) pixel, the CIS pixel comprising:
a photoelectric conversion device configured to generate charges corresponding to an incident light that is incident on the CIS pixel; and
a readout circuit configured to generate an output voltage corresponding to the charges;
a dynamic vision sensor (DVS) pixel configured to detect a change in intensity of the incident light based on the charges generated by the photoelectric conversion device, and output an event signal based on the change in intensity; and
an image signal processor configured to selectively control the image sensor to generate first image data of the image sensor based on the output voltage generated by the CIS pixel and generate second image data based on the event signal generated by the DVS pixel,
wherein the CIS pixel further comprises:
a transfer transistor configured to transfer the charges generated by the photoelectric conversion device to a floating diffusion node; and
a reset transistor configured to reset a voltage of the floating diffusion node in a first mode to generate the first image data of the image sensor based on the output voltage generated by the CIS pixel and connect the floating diffusion node to the DVS pixel in a second mode to generate the second image data based on the event signal generated by the DVS pixel, and
wherein the readout circuit comprises:
a drive transistor configured to output the voltage of the floating diffusion node as the output voltage in the first mode; and
a select transistor configured to select the CIS pixel in the first mode.
2. The image sensor of claim 1 , wherein the CIS pixel further comprises:
a transfer transistor configured to transfer the charges generated by the photoelectric conversion device to a floating diffusion node, in a first mode to generate the first image data of the image sensor based on the output voltage generated by the CIS pixel;
a reset transistor configured to reset a voltage of the floating diffusion node, in the first mode; and
a switch transistor configured to transfer the charges to the DVS pixel, in a second mode to generate the second image data based on the event signal generated by the DVS pixel, and
wherein the readout circuit comprises:
a drive transistor configured to output the voltage of the floating diffusion node as the output voltage in the first mode; and
a select transistor configured to select the CIS pixel in the first mode.
3. The image sensor of claim 1 , wherein the CIS pixel further comprises:
a transfer transistor configured to transfer the charges generated by the photoelectric conversion device to a floating diffusion node;
a reset transistor configured to reset a voltage of the floating diffusion node, in a first mode to generate the first image data of the image sensor based on the output voltage generated by the CIS pixel; and
a switch transistor configured to transfer the charges transferred to the floating diffusion node to the DVS pixel in a second mode to generate the second image data based on the event signal generated by the DVS pixel,
wherein the readout circuit comprises:
a drive transistor configured to output the voltage of the floating diffusion node as the output voltage in the first mode; and
a select transistor configured to select the CIS pixel in the first mode.
4. The image sensor of claim 1 , wherein the CIS pixel further comprises:
a reset transistor configured to reset a voltage of a floating diffusion node in a first mode to generate the first image data of the image sensor based on the output voltage generated by the CIS pixel and transfer the voltage of the floating diffusion node to the DVS pixel in a second mode to generate the second image data based on the event signal generated by the DVS pixel, and
wherein the readout circuit comprises:
a drive transistor configured to output the voltage of the floating diffusion node as the output voltage in the first mode; and
a select transistor configured to select the CIS pixel in the first mode.
5. The image sensor of claim 1 , wherein the CIS pixel further comprises:
a transfer transistor configured to transfer the charges to a floating diffusion node; and
a reset transistor configured to reset a voltage of the floating diffusion node in a first mode to generate the first image data of the image sensor based on the output voltage generated by the CIS pixel and connect the floating diffusion node to the DVS pixel in a second mode to generate the second image data based on the event signal generated by the DVS pixel,
wherein the readout circuit comprises:
a drive transistor configured to output the voltage of the floating diffusion node as the output voltage in the first mode, and a first select transistor configured to select the CIS pixel in the first mode; and
a second select transistor configured to control activation of the transfer transistor, in the first mode and the second mode.
6. The image sensor of claim 1 , wherein the photoelectric conversion device is a first photoelectric conversion device,
wherein the CIS pixel further comprises:
a second photoelectric conversion device configured to generate second charges corresponding to the incident light that is incident on the CIS pixel;
a first transfer transistor configured to transfer the charges generated by the first photoelectric conversion device to a floating diffusion node;
a second transfer transistor, configured to transfer the second charges generated by the second photoelectric conversion device to the floating diffusion node; and
a reset transistor configured to reset a voltage of the floating diffusion node in a first mode to generate the first image data of the image sensor based on the output voltage generated by the CIS pixel and connect the floating diffusion node to the DVS pixel in a second mode to generate the second image data based on the event signal generated by the DVS pixel, and
wherein the readout circuit comprises:
a drive transistor configured to reset the voltage of the floating diffusion node as the output voltage in the first mode; and
a select transistor configured to select the CIS pixel in the first mode.
7. The image sensor of claim 1 , wherein the DVS pixel comprises:
a photoreceptor configured to output a log voltage based on a photocurrent corresponding to the charges generated by the photoelectric conversion device; and
a DVS pixel back-end circuit configured to amplify the log voltage, compare the amplified log voltage to a comparison voltage, determine the change in intensity based on a result of comparing the amplified log voltage to the comparison voltage, and output the event signal based on the change in intensity.
8. The image sensor of claim 1 , wherein the CIS pixel comprises a plurality of CIS pixels, and
wherein, when the DVS pixel operates, the DVS pixel is configured to receive the charges from a plurality of photoelectric conversion devices of the plurality of CIS pixels.
9. The image sensor of claim 1 , further comprising:
a first substrate on which a CIS pixel array including the CIS pixel is formed; and
a second substrate on which a DVS pixel array including the DVS pixel is formed,
wherein the first substrate and the second substrate are connected in a Cu-to-Cu bonding manner.
10. The image sensor of claim 1 , wherein the DVS pixel does not include any photoelectric conversion device.
11. An image sensor comprising:
a complementary metal-oxide semiconductor image sensor (CIS) pixel, the CIS pixel comprising:
a photoelectric conversion device configured to generate charges corresponding to an incident light that is incident on the CIS pixel;
a drive transistor, the drive transistor comprising a gate electrode connected to a floating diffusion node to which the charges generated by the photoelectric conversion device are transferred; and
a reset transistor configured to reset a voltage of the floating diffusion node;
a dynamic vision sensor (DVS) pixel, the DVS pixel comprising a log current source, the DVS pixel configured to detect a change in intensity of the incident light based on the charges generated by the photoelectric conversion device, and output an event signal based on the change in intensity; and
an image signal processor configured to connect a gate electrode of the reset transistor and an end of the drive transistor to the log current source.
12. The image sensor of claim 11 , further comprising a switching circuit configured to:
selectively apply a reset signal to the gate electrode of the reset transistor and a power supply voltage to the end of the drive transistor, in a first mode to generate first image data of the image sensor based on an output voltage generated by the CIS pixel, and
connect the gate electrode of the reset transistor and the end of the drive transistor to the log current source, in a second mode to generate second image data based on the event signal generated by the DVS pixel.
13. The image sensor of claim 12 , wherein the CIS pixel further comprises:
a transfer transistor configured to transfer the charges generated by the photoelectric conversion device to the floating diffusion node; and
a select transistor configured to select the CIS pixel in the first mode,
wherein the output voltage is output from an opposite end of the drive transistor that is opposite from the end of the drive transistor.
14. The image sensor of claim 11 , wherein the DVS pixel does not include any photoelectric conversion device.
15. An image sensor comprising:
a first substrate on which a CIS pixel array comprising a plurality of CMOS image sensor (CIS) pixels is formed, each CIS pixel of the CIS pixel array comprising:
a photoelectric conversion device configured to generate charges corresponding to an incident light that is incident on the CIS pixel; and
a readout circuit configured to generate an output voltage corresponding to the charges generated by the photoelectric conversion device;
a second substrate on which a DVS pixel array comprising a plurality of dynamic vision sensor (DVS) pixels is formed, each DVS pixel of the DVS pixel array configured to detect a change in intensity of the incident light based on the charges generated by the CIS pixel array to output an event signal based on the change in intensity; and
an image signal processor configured to selectively control the image sensor to generate first image data of the image sensor based on the output voltage and generate second image data based on the event signal generated by the DVS pixel array,
wherein each CIS pixel of the CIS pixel array comprises:
a transfer transistor configured to transfer the charges generated by the photoelectric conversion device to a floating diffusion node; and
a reset transistor configured to reset a voltage of the floating diffusion node in a first mode to generate the first image data of the image sensor based on output voltages output by the CIS pixel array and connect the floating diffusion node to the DVS pixel, from among the DVS pixel array, in a second mode to generate the second image data based on event signals generated by the DVS pixel array, and
wherein the readout circuit comprises:
a drive transistor configured to output the voltage of the floating diffusion node as the output voltage in the first mode; and
a select transistor configured to select the CIS pixel in the first mode.
16. The image sensor of claim 15 , wherein each DVS pixel of the DVS pixel array comprises:
a photoreceptor configured to output a log voltage based on a photocurrent corresponding to the charges generated by the photoelectric conversion device; and
a DVS pixel back-end circuit configured to amplify the log voltage, compare the amplified log voltage to a comparison voltage, determine the change in intensity based on a result of comparing the amplified log voltage to the comparison voltage, and output the event signal based on the change in intensity.
17. The image sensor of claim 15 , wherein each DVS pixel of the DVS pixel array does not include any photoelectric conversion device.
18. The image sensor of claim 15 , wherein the first substrate and the second substrate are connected in a Cu-to-Cu bonding manner.