
4
3. DVC Camera Functional Description
3.1 CCD Sensor:
Light from the scene is brought into focus at the imaging plane of the CCD. An optical block
(optional) filters out the IR component of the light.
The following functions take place within the CCD:
3.1.1 Integration:
During the integration period (1/60 sec.), charges are integrated in the active pixel wells of the
Imaging Area. The amount of charge that is integrated in each active pixel well is proportional to
the illumination received at each active pixel site on the CCD. Anti-blooming pulses during the
horizontal and vertical blanking areas trigger the anti-blooming gates that are an integral part of
the active pixel elements.
3.1.2 Parallel Transfer:
During the Vertical Blanking interval, the entire charge matrix that was integrated in the previous
field (1/60 sec) is shifted to the opaque storage area of the CCD. This is accomplished by a
series of 242 pulses, each of which causes the charge matrix to shift down by one line. This
process takes approximately 68
µ
sec.
3.1.3 Readout:
In the following field, the charges are transferred from the storage area of the CCD to on-chip
serial shift registers and then sequentially to the detection nodes where they are made available
as signal voltages. Note: While one field is being read out from the Storage Area, the other field
is being integrated in the Imaging Area of the CCD.
3.2 Video Pre-processing:
The low-level video signal voltage from the CCD is fed through a high-speed sample-and-hold
amplifier, clamped (for black reference) and amplified before further video processing. It is in
CCD Sensor
3 Channel
S/H
3 Channel pre-
amplifier:
Gain
Clam ping
White Balance
Black Balance
3 : 1
Analog
multiplexer
Digital Video Amp:
Digital Gain
Digital Offset
Video Processor:
Gain & Offset
Gamma
Sync Insertion
(optional)
AD-10 or AD-08
board:
Analog/Digital
conversion
TTL to RS-422
drivers:
single ended TTL
to parallel,
differential, RS-
422
Linear Voltage
Regu lators
Imaging
Area
Storage
Area
Timing and control logic:
Clock generation
Generation of all CCD control signals
Genlock PLL (optional)
Ex posure control
Sensor and Video Board
Sync & Power Board
Analog to Digital Board
RS-170 Output
Processed
Analog Video
Multiplex ed
Analog Video
Pre-amp
Video
CCD
Video
Serial
Parallel
S/H signals
Clam p
Multiplex signals
Clock
Clock, Enable Line, Enable Frame, Field
I d
+12V, -12V, +5V
DIN Connector
(Power Supply)
DB-37
connector
(Digital Video)
Digital Video
(8 or 10 bits)
Serial
Driver
Parallel
Driver
Figure 3-1: Digital Camera Block Diagram
Summary of Contents for DigitEyes Series
Page 14: ...9 Figure 4 3 TC 245 Gate Level Drawing Texas Instruments 1994 ...
Page 61: ...56 12 Appendix D Camera Mechanical Drawings Figure 12 1 Camera Mechanical Drawings ...
Page 63: ...58 Figure 13 2 Camera Noise Spectrum Min Gain Bandwidth 10kHz to 4 2MHz ...
Page 64: ...59 Figure 13 3 Camera Noise Spectrum Max Gain Bandwidth 100kHz to 4 2Mhz ...
Page 65: ...60 Figure 13 4 Camera Noise Spectrum Max Gain Bandwidth 10kHz to full ...