Super Fast Camera System Supervised by: Leonid Boudniak Performed by: Tokman Niv Levenbroun Guy

Project Objective Create Super fast digital camera, to capture fast events, by combining several basic, off the shelf, image sensors. Create Super fast digital camera, to capture fast events, by combining several basic, off the shelf, image sensors.

Abstract In order to capture fast events, a very high frame rate is required (~500K fps). In order to capture fast events, a very high frame rate is required (~500K fps). However, since the events are, usually, very short, only a few frames (<100) are required. However, since the events are, usually, very short, only a few frames (<100) are required. Frame rate in most image sensors is about fps,due to slow read out process of the image. Frame rate in most image sensors is about fps,due to slow read out process of the image.

Solutions Solution 1: using a high speed camera. Expensive. Solution 1: using a high speed camera. Expensive. Solution 2: using several cameras. Solution 2: using several cameras. Solution 3: using several sensors, each captures only a single frame. Solution 3: using several sensors, each captures only a single frame. Solution 4: using less sensors, each with capability of capturing several images within one frame - multi framing (?) Solution 4: using less sensors, each with capability of capturing several images within one frame - multi framing (?)

Block diagram

Project Goals Choose an appropriate image sensor, to fit our goals. Choose an appropriate image sensor, to fit our goals. Design a controller to operate a single and two sensors. Design a controller to operate a single and two sensors. Simulate the sensor, and test the controller operation. Simulate the sensor, and test the controller operation.

Added Values Understand the fundamentals of image sensors currently at the market. Understand the fundamentals of image sensors currently at the market. Learn VHDL syntax, proper programming, and writing methods for synthesis. Learn VHDL syntax, proper programming, and writing methods for synthesis. Basic concepts of system design. Basic concepts of system design. Working with FPGA platform. Working with FPGA platform.

Choosing the sensor - Fill factor The amount of photons, influencing the photo diode. The amount of photons, influencing the photo diode.

Choosing the sensor – Quantum Efficiency/ Responsivity Choosing the sensor – Quantum Efficiency/ Responsivity The amount of electrons generated, for each photon hitting the photo diode. The amount of electrons generated, for each photon hitting the photo diode.

Choosing the sensor - Shutter Shutter can be either: Shutter can be either: Uniform: light collection starting and ending at exactly the same time for all pixels. Uniform: light collection starting and ending at exactly the same time for all pixels. Rolling : All pixels in one row of the imager collect light during exactly the same period of time, but the time light collection starts and ends is slightly different for each row. Rolling : All pixels in one row of the imager collect light during exactly the same period of time, but the time light collection starts and ends is slightly different for each row. For short integration time, uniform shutter is important. For short integration time, uniform shutter is important.

Choosing the sensor - Gain Fast exposure means smaller number of electrons collected, resulting in low voltage. Increasing the voltage increase the sensor ’ s sensitivity. Fast exposure means smaller number of electrons collected, resulting in low voltage. Increasing the voltage increase the sensor ’ s sensitivity.

Choosing The Sensor, summary High Fill Factor. High Fill Factor. Low system complexity. Low system complexity. Uniform shutter. Uniform shutter. High shutter speed (~2us). High shutter speed (~2us). Good Responsivity, fast integration. Good Responsivity, fast integration. High Gain. High Gain. Problem :sensors data sheet usually don ’ t specify shutter speed or minimal integration time. Problem :sensors data sheet usually don ’ t specify shutter speed or minimal integration time.

Cmos Vs. CCD CmosCCDfeature Digitized bits Analog Voltage Output signal LowHigh System complexity Chip + lens PCB + multiple chips + lens Camera components Slightly better ModerateResponsivity higher Moderate to high Speed Single, low- voltage Multiple, higher voltage Biasing and Clocking

CCD Vs. Cmos conclusions Even though CCD is more widespread, and of better image quality, it seems that Cmos sensors are more suitable for our purposes. Even though CCD is more widespread, and of better image quality, it seems that Cmos sensors are more suitable for our purposes. The high advantage is the complexity of the system, needed for CCD sensors, which is already integrated in the Cmos sensor. The high advantage is the complexity of the system, needed for CCD sensors, which is already integrated in the Cmos sensor. Cmos CCD `

Multi-framing DRS Technologies offer ultra fast cameras, with 8-68 independent small (520x520) images at an incrediable frame rate. DRS Technologies offer ultra fast cameras, with 8-68 independent small (520x520) images at an incrediable frame rate. It was believed that these cameras split the sensor to smaller sub sections, exposing each at a different time to allow the fast frame rate. It was believed that these cameras split the sensor to smaller sub sections, exposing each at a different time to allow the fast frame rate. After studying CCD image sensor, we have come to believe that such structure is extremly complicated, and is not available as “ of the shelf ” sensor. After studying CCD image sensor, we have come to believe that such structure is extremly complicated, and is not available as “ of the shelf ” sensor. Those cameras are either using several indepentnt sensors, or using a custom made sensor with large storage area. Those cameras are either using several indepentnt sensors, or using a custom made sensor with large storage area.

STORAGE AREA Multi-framing (cont ’ ) Example of large storage area usage: Example of large storage area usage: Line register Frame 1 Frame 2 Frame 1 Frame 2 Frame 3 Frame 1 Frame 2 Frame 3 Frame 4 DRS Technologies has been contacted about this subject

Possible CMOS sensors Micron 1.3 Megapixel Micron 1.3 Megapixel MT9M413Model 2us-1.3s Shutter time 13uV/eGain Amplifiers, ADC On-chip features Digital Output type

Possible CMOS sensors FillFactory 1.3 Megapixel FillFactory 1.3 Megapixel Lupa 1300 Model ≥2us Shutter time 16uV/eGain Amplifiers On-chip features Analog. Output type

Project Schedule Part one: choosing the sensor: 4 weeks. Part one: choosing the sensor: 4 weeks. Part two: electric schematics : 1.5 weeks. Part two: electric schematics : 1.5 weeks. Part three: learn VHDL : 1.5 weeks. Part three: learn VHDL : 1.5 weeks. Part four: programming the controller : 4 weeks. Part four: programming the controller : 4 weeks. Part five: simulation and testing : 3 weeks. Part five: simulation and testing : 3 weeks.