Imaging systems with integrated stereo imagers
View Patent ↗An imaging system may include an integrated stereo imager that includes first and second imager arrays on a single integrated circuit. Image readout circuitry may be located between the first and second imager arrays and a horizontal electronic rolling shutter may be used to read image data out of the arrays. The layout of the arrays and image readout circuitry on the integrated circuit may help to reduce the size of the integrated circuit while maximizing the baseline separation between the arrays. Memory buffer circuitry may be used to convert image data from the arrays into raster-scan compliant image data. The raster-scan compliant image data may be provided to a host system.
1. A stereoscopic camera module for an electronic device, the stereoscopic camera module comprising:
an integrated circuit that comprises:
a first array of image sensing pixels arranged in columns and rows;
a second array of image sensing pixels arranged in columns and rows; and
image readout circuitry located between the first and second arrays using a horizontal electronic rolling shutter that reads image data out of the first and second arrays by reading out image data from individual columns of image sensing pixels over horizontal output line, wherein each of the horizontal output lines is coupled to the image sensing pixels in a respective one of the rows of the first and second arrays;
a first address circuit that generates column select signals that couple a selected one of the columns of image sensing pixels in the first array to the image readout circuitry; and
a second address circuit that generates column select signals that couple a selected one of the columns of image sensing pixels in the second array to the image readout circuitry.
2. The stereoscopic camera module defined in claim 1 further comprising:
memory buffer circuitry that is coupled to the integrated circuit, that receives non-raster-scan image data from the first and second arrays of image sensing pixels, and that outputs raster-scan image data.
3. The stereoscopic camera module defined in claim 2 wherein the memory buffer circuitry comprises double frame memory buffer circuitry that has a storage capacity sufficient to simultaneously store two complete stereo images from the first and second arrays of image sensing pixels.
4. An electronic device comprising:
an imaging system that comprises:
a first array of image sensing pixels;
image readout circuitry that reads non-raster-scan image data image data out of the first array with a horizontal electronic rolling shutter; and
memory buffer circuitry that buffers the non-raster-scan image data using a first portion of the memory buffer circuitry and converts the non-raster-scan image data into raster-scan compliant image data that is read out from a second portion of the memory buffer circuitry that is different than the first portion of the memory buffer circuitry.
5. The electronic device defined in claim 4 wherein the imaging system further comprises a second array of image sensing pixels and wherein the image readout circuitry reads non-raster-scan image data out of the second array with a horizontal electronic rolling shutter.
6. The electronic device defined in claim 5 wherein the electronic device comprises an endoscope having an elongated housing.
7. The electronic device defined in claim 5 wherein the first array, the second array, and the image readout circuitry are located on an integrated circuit.
8. The electronic device defined in claim 7 wherein the image readout circuitry is located between the first and second arrays on the integrated circuit.
9. The electronic device defined in claim 8 wherein the image sensing pixels are arranged in columns and rows in the first and second arrays and wherein the integrated circuit comprises:
a first address circuit that generates column select signals that couple a selected one of the columns of image sensing pixels in the first array to the image readout circuitry; and
a second address circuit that generates column select signals that couple a selected one of the columns of image sensing pixels in the second array to the image readout circuitry.
10. The electronic device defined in claim 7 wherein the electronic device comprises a first portion that is disposable and a second portion that is reusable, wherein the first and second portions are nondestructively coupled together, wherein the integrated circuit is located within the first portion, and wherein the memory buffer circuitry is located within the second portion.
11. The electronic device defined in claim 5 wherein the memory buffer circuitry comprises double frame memory buffer circuitry that has a storage capacity sufficient to simultaneously store two complete stereo images from the first and second arrays of image sensing pixels.
12. The electronic device defined in claim 5 wherein the image readout circuitry comprises a plurality of analog-to-digital converters.
13. A method for producing raster-scan compliant images using a sensor array that is read out using a horizontal electronic rolling shutter, the method comprising:
with the sensor array, generating non-raster-scan image data associated with a given image;
with memory buffer circuitry, buffering the non-raster-scan image data associated with the given image, wherein the memory buffer circuitry comprises double frame memory buffer circuitry;
after the non-raster-scan image data associated with the given image is buffered in the memory buffer circuitry, outputting raster-scan image data associated with the given image using the memory buffer circuitry; and
while the raster-scan image data associated with the given image is being outputted, generating non-raster-scan image data associated with a second given image using the sensor array.
14. The method defined in claim 13 further comprising:
while the raster-scan image data associated with the given image is being outputted, buffering the non-raster-scan image data associated with the second given image with the double frame memory buffer circuitry; and
after the non-raster-scan image data associated with the second given image is buffered in the memory buffer circuitry and after the raster-scan image data associated with the given image is outputted, outputting raster-scan image data associated with the second given image with the double frame memory buffer circuitry.
15. The method defined in claim 13 wherein the sensor array comprises first and second sensor arrays on an integrated circuit, wherein the integrated circuit comprises image readout circuitry located between the first and second arrays, wherein image sensing pixels in the first and second arrays are arranged in columns and rows, and wherein generating the non-raster-scan image data associated with the given image with the sensor array comprises:
using a horizontal electronic rolling shutter to read image data from the columns of the image sensing pixels one column at a time.