Highly miniaturized, battery operated, digital wireless camera using programmable single chip active pixel sensor (APS) digital camera chip

• US 8,085,342 B2
• Filed: 12/14/2007
• Issued: 12/27/2011
• Est. Priority Date: 12/22/1998
• Status: Expired due to Fees

• Current Assignee: California Institute of Technology
• Original Assignee: California Institute of Technology
• Inventors: Agan, Martin J., Fossum, Eric R., Nixon, Bob H., Olson, Brita H., Pain, Bedabrata, Pasqualino, Chris, Satorius, Ed H., Shaw, Tim J., Stevens, Gary L.
• Primary Examiner(s): Jerabek, Kelly L
• Application Number:
  US11/957,394
• Publication Number:
  US 20090122169A1
• Time in Patent Office: 1,474 Days
• Field of Search: 348/211.99, 348/211.1, 348/211.2, 348/211.5, 348/372
• US Class Current: 348/372
• CPC Class Codes: H04N 23/50 Constructional details
• CPC Class Codes: H04N 23/57 Mechanical or electrical details of cameras or camera modules specially adapted for being embedded in other devices
• CPC Class Codes: H04N 23/651 for reducing power consumption by affecting camera operations, e.g. sleep mode, hibernation mode or power off of selective parts of the camera
• CPC Class Codes: H04N 23/66 Remote control of cameras or camera parts, e.g. by remote control devices

Abstract

A miniaturized camera which is programmable and provides low power consumption. An active pixel image sensor used in the highly miniaturized camera provides improved imaging functionality as well as reduced power consumption, extending the possible life time of the camera system. The spread spectrum nature of transmission and reception improves data integrity as well as data security. The ability of the highly miniaturized wireless camera to receive commands as well as transmit image data provides improved functionality and a variable rate of power consumption to be set according to the application and needs of the situation.

Claims

1. A single-chip wireless camera comprising;

a receiving element to wirelessly receive external command signals from a remote device, wherein the external command signals comprise;

a command to switch between multiple modes of operations comprising an operating state, a receiving state and a sleep state, and

a programmable command to program said camera to perform one or more imaging operations corresponding to the modes of operations;

an active pixel sensor having a plurality of addressable units, each said unit associated with a pixel processing element;

active pixel sensor control circuitry, including circuiting that addresses and controls reading operation of the active pixel sensor;

a power management element to support the operating state in which circuitry of the chip is powered, the receiving state in which the receiving element is powered once within a duration of time, and the sleep state in which most circuitry is unpowered; and

a programmable control logic coupled to the receiving element and the active pixel sensor, operating to respond to the received command signals and to control an amount of battery consumption used by said camera by performing the following;

responsive to the received command to switch between the multiple modes of operation, switching between the operating state, the receiving state and the sleep state to allocate power among components of said camera including the receiving element and the active pixel sensor, and

responsive to the received programmable command, editing an image signal received from the active pixel sensor by performing the one or more imaging operations selected from a group consisting of;

subsampling said active pixel sensor, the subsampling comprising powering fewer than all of the plurality of addressable units to receive an entirety of an overall image in a reduced resolution,

windowing said active pixel sensor to receive a subset of the overall image by powering only a corresponding subset of the active pixel sensor, and

altering an exposure time to control brightness and contrast of the entirety or the subset of the overall image.

2. The camera of claim 1 further comprising a transmitter.

3. The wireless camera system of claim 1 where the command signals are digital signals and the active pixel sensor circuitry logic converts at least one of the digital command signals to an analog signal to operate the active pixel sensor.

4. The wireless camera system of claim 1 where the camera consumes less power while in the sleep state than while operating in the operating state and the receiving state, and

where the camera consumes less power while operating in the receiving state than while operating in the operating state.

5. The single-chip wireless camera of claim 1, wherein the plurality of addressable units in the active pixel sensor are arranged in an array of rows and columns, wherein powering fewer than all of the plurality of addressable units comprises powering fewer than all of the addressable units in each row and in each column.

6. The single-chip wireless camera of claim 5, wherein powering fewer than all of the plurality of addressable units in each row and in each column comprises powering alternate addressable units in each row and in each column.

7. The single-chip wireless camera of claim 1, wherein the programmable control logic comprises circuits for performing different functions based on the modes of operations of the camera.

8. The single-chip wireless camera of claim 1, wherein the programmable control logic comprises circuitry to capture still images and continuous images.

9. A camera comprising:

a casing;

a lens mounted in the casing;

an electrical connection for a battery, inside the casing;

a transmitting antenna mounted on the casing;

a receiving antenna mounted on the casing;

a receiver to wirelessly receive external command signals, wherein the external command signals comprise;

a command to switch between multiple modes of operations comprising an operating state, a receiving state and a sleep state, and

a programmable command to program said camera to perform one or more imaging operations corresponding to the modes of operations;

an active pixel sensor having a plurality of addressable units, each said unit associated with a photogate-type photosensitive element, inside the casing, optically coupled to the lens and electrically coupled to the battery;

a power management element to support the operating state in which circuitry of the chip is powered, the receiving state in which the receiving element is powered once within a duration of time, and the sleep state in which most circuitry is unpowered; and

a programmable control logic inside the casing and coupled to the transmitting antenna, the receiving antenna, the active pixel sensor, and the electrical connection, said programmable control logic, to respond to the received command signals and to control operation of the camera and an amount of battery consumption used by the camera by performing the following;

responsive to the received command to switch between the multiple modes of operation, switching between the operating state, the receiving state and the sleep state to allocate power among components of said camera including the receiving element and the active pixel sensor, and

responsive to the received programmable command, editing an image signal received from the active pixel sensor by performing the one or more imaging operations selected from a group consisting of;

subsampling said active pixel sensor, the subsampling comprising powering fewer than all of the plurality of addressable units to receive an entirety of an overall image in a reduced resolution,

windowing said active pixel sensor to receive a subset of the overall image by powering only a corresponding subset of the active pixel sensor, and

altering an exposure time to control brightness and contrast of the entirety or the subset of the overall image based on a given mode of operation.

10. The camera of claim 9 where the active pixel sensor is a single integrated circuit comprising:

a pixel matrix of photogate-type photosensitive elements;

a row driver and decoder coupled to the pixel matrix;

a column decoder coupled to the pixel matrix;

a plurality of analog to digital converters coupled to the pixel matrix and each associated with a unit of the pixel matrix;

at least one digital to analog converter coupled to the pixel matrix; and

a control and timing circuit coupled to the row driver and decoder, the column decoder, the analog to digital converter, and the digital to analog converter.

11. The camera of claim 9 where the volume of the camera as a whole is not more than approximately four cubic inches.

12. A wireless camera system including the camera of claim 9 and further comprising a base station, where the base station receives signals transmitted from the camera and transmits the external command signals to be received by the camera.

13. The wireless camera system of claim 12 where the camera consumes less power while in the sleep state than while operating in the operation state and the receiving state, and

wherein the camera consumes less power while operating in the receiving state than while operating in the operation state.

14. The wireless camera system of claim 12 where when the camera is in the sleep state, the programmable control logic allocates power so that power is supplied through the electrical connection only to those components of the camera necessary to maintain the idle mode and be able to change to a different mode.

15. The camera of claim 9, wherein the plurality of addressable units in the active pixel sensor are arranged in an array of rows and columns, and wherein powering fewer than all of the plurality of addressable units comprises powering fewer than all of the addressable units in each row and in each column.

16. The camera of claim 15, wherein powering fewer than all of the plurality of addressable units in each row and in each column comprises powering alternate addressable units in each row and in each column.

17. The camera of claim 9, wherein the programmable control logic comprises circuits for performing different functions based on the modes of operations of the camera.

18. The camera of claim 9, wherein the programmable control logic comprises circuitry to capture still images and continuous images.