A Presentation on Charged Coupled Device (CCD). Presented By: Adwitiya Biswas Ankit Prasad Priyanka Kumari Students of Asansol Engineering College. 3rd Year Applied Electronics and Instrumentation Engineering.

1. PRESENTED BY:
 ADWITIYA BISWAS
 ANKIT PRASAD
 PRIYANKA

2.  A charged coupled device(CCD) is a device for the
movement of electrical charge, usually from within
the device to an area where the charge can be
manipulated .

3. The CCD is divided into a large number of light-sensitive small
areas known as PIXELS.
Light Sensitive Area
Typical Size of a CCD: 1024 Pixels High * 1024 Pixels wide.

4. Material of CCD: METAL OXIDE SEMICONDUCTOR

5. The four primary stages of image generation in a CCD are:
 Charge generation(light to charge conversion)
 Collection and storage of the charge
 Charge transfer
 Charge measurement
HOW DOES CHARGE TRANSFER TAKE PLACE?

6. STEP 1
STEP 3
STEP 5
STEP 4
STEP 6
S
T
E
P
2

7. The final process on the CCD is the reading of each pixel so
that the size of the associated charge cloud can be measured.
At the end of the readout register is an amplifier which
measure the value of each charge cloud and converts it into a
voltage, a typical conversion factor being around 5-10µV per
electron with "typical" full well values being about 100,000
electrons or so.

8. CCD CMOS
In a CCD device, the charge
is actually transported
across the chip and read at
one corner of the array. An
analog-to-digital converter
turns each pixel's value into
a digital value.
In most CMOS devices, there
are several transistors at
each pixel that amplify and
move the charge using more
traditional wires. The CMOS
approach is more flexible
because each pixel can be
read individually.

9. THE COMMON TYPES OF CCD ARE:
 Interline transfer device
 Full frame transfer device
 Intensified charged coupled device

10.  During integration only one line receives light. At the end ,this line
is shifted to the protected line, where it will be read by the
computer. An interleing transfer device can be used with planetary
photography ,lunar photography.

11.  Full Frame CCDs are inherently progressive scan. They capture
a full frame in a single shutter (integration) period. They differ
from Interline Transfer CCDs because they do not have a pixel
storage area next to the active pixel. They in fact have no
pixel storage area.
 The benefit of Full Frame sensors is that they have 100% Fill
Factor and since they require half as much pixel area as Frame
Transfer sensors they are less expensive.
 The disadvantage of Full Frame sensors is that it takes a
relatively long time to clock the pixels out of the shift register
and so the effective Readout Time is long. Full Frame sensors
are always used with a mechanical shutter or strobe light.

13.  It is a CCD that is fibre optically connected to micro channel
plate(MCP) to increase sensitivity.
 A photo cathode converts photon to electron
 After the MCP a phosphor screen converts the electrons back to
photons which are fibre optically guided to the CCD.
 Image intensifiers were initially developed for night vision
applications by the Military.

14.  CCDS are used in digital cameras ,optical scanners and video
cameras as light-sensing devices.
 CCD cameras used in astrophotography.
 CCDS are typically sensitive to infrared light, which allows
infrared photography, night-version devices and video-
recording/photography.
 CCD are use to take exposures of galaxies.

16.  CCD sensors are more susceptible to vertical smear from
bright light sources when the sensor is overloaded; high-
end frame transfer CCDs in turn do not suffer from this
problem.
 CCD cameras are designed for specific use, and knowing
what you’ll be asking of it will help you make your
purchasing decision. CCD cameras are manufactured with
c-mount or t-mounts and are also equipped with an
adaptor to connect to a computer for ease in displaying
the images

17.  CCD sensors consume much much more power.
 HD video-less pixel rates.
 CCDS are expensive as they require special manufacturing.
 CCD sensors are rigid and can irritate the oral tissue and
cause pain.
 The receptors is reused indefinitely-cross infection.
 CCD sensors may be wired/wireless-mastering the use
requires some effort and learning period.

18. THANK YOU