CCD vs CMOS!

5,637 views
5,349 views

Published on

Published in: Art & Photos, Business

CCD vs CMOS!

  1. 1. CCD VS CMOS! Henry Lau
  2. 2. What on earth is it?! <ul><li>CCD (Charged coupled device) and CMOS (complementary metal oxide semiconductor) are both Integrated circuits which have many uses in today's world. Since their functions are closely related they are often compared with each other especially by companies trying to win over customers. </li></ul>
  3. 3. What are they used for? <ul><li>CCD </li></ul><ul><li>Cell phone cameras </li></ul><ul><li>Space telescopes </li></ul><ul><li>Video cameras </li></ul><ul><li>SLR cameras </li></ul><ul><li>CMOS </li></ul><ul><li>Cell phone cameras </li></ul><ul><li>Microprocessors </li></ul><ul><li>Digital logic circuits </li></ul><ul><li>Video cameras </li></ul><ul><li>SLR cameras </li></ul>
  4. 4. How does it work? <ul><li>CCD and CMOS work the say way through detecting light and converting the light signal into electrical signals (electrons). The IC (integrated circuit) is a semiconductor made of silicon which can effectively absorb photons (light) through a panel. The panel is made of thousands of tiny diodes called photosites, this creates the image through recording the light intensity of each diode. A brighter image will contain more electrical charges than a low light image would. </li></ul>
  5. 5. What about colour? <ul><li>This also happens during the same time the ICs absorb the photons. In digital terms all colours can be created through the process of mixing 3 colours Red, Green and Blue. These colours are specifically labelled through the values from 0-255. The ICs basically do the same thing by filtering out each photosite for a specific colour. They’re placed in patterned checkerboard to evenly absorb the correct colour as much as possible. In some cases there are 3 ICs along with a beam splitter for 3 different versions of the same image to allow a whole chip to take on a full colour for itself, this is then blended back together to create a very high quality full colour image. </li></ul>
  6. 6. CCD <ul><li>Advantages </li></ul><ul><li>Less interference from noise </li></ul><ul><li>Usually better quality as it has been mass produced for a long period of time. </li></ul><ul><li>Can create very high quality sensors. </li></ul><ul><li>Excellent light sensitivity. </li></ul><ul><li>Higher quantum efficiency than CMOS. </li></ul><ul><li>Disadvantages </li></ul><ul><li>Consumes more power than CMOS (100 times more!) </li></ul><ul><li>A lot more expensive than CMOS. </li></ul><ul><li>Shorter battery life. </li></ul><ul><li>Circuit parts absorb some light resulting in lower quality. </li></ul><ul><li>Majority of blue photons absorbed before it reaches the chip. </li></ul><ul><li>Can cause an unwanted bloom effect due to overfilling the buckets (photosites). </li></ul>
  7. 7. CMOS <ul><li>Advantages </li></ul><ul><li>So much cheaper than CCD due to power usage. </li></ul><ul><li>Production materials are cheap compared to CCD. </li></ul><ul><li>quality is catching up to CCDs as technology is improving. </li></ul><ul><li>Much better battery life than CCD. </li></ul><ul><li>No accidental bloom effects. </li></ul><ul><li>Disadvantages </li></ul><ul><li>More likely to be affected by noise due to the manufacturing process affecting the ability to transport charge across the IC creating grainy images. </li></ul><ul><li>Typically the quality isn’t as good as CCD. </li></ul><ul><li>lower quantum efficiency making images lower quality in low light conditions. </li></ul>
  8. 8. Conclusion <ul><li>Judging from the facts and advantages from each IC, it all depends on consumer’s use to determine what type they would use. For example, a standard consumer who would want a budget camera which could take a decent quality image without little hassles (battery life) a CMOS would be an ideal choice, whereas a professional photographer who would want the highest quality image would pick a one with a CCD. However camera companies are most focused on selling the product itself despite its specifications, which may mislead consumers. </li></ul>
  9. 9. More examples <ul><li>Check out the videos below  </li></ul>
  10. 10. Bibliography <ul><li>CMOS Rolling Shutter. 2012. CMOS Rolling Shutter . [ONLINE] Available at: http:// www.dvxuser.com/jason/CMOS -CCD/ . [Accessed 22 February 2012]. </li></ul><ul><li>What Is A CCD?- charge coupled device. 2012. What Is A CCD?- charge coupled device . [ONLINE] Available at: http:// www.specinst.com/What_Is_A_CCD.html . [Accessed 22 February 2012]. </li></ul><ul><li>HowStuffWorks &quot;How Camcorders Work&quot;. 2012. HowStuffWorks &quot;How Camcorders Work&quot; . [ONLINE] Available at: http://electronics.howstuffworks.com/camcorder2.htm . [Accessed 22 February 2012]. </li></ul><ul><li>HowStuffWorks &quot;Cameras: Film and Photography Basics&quot;. 2012. HowStuffWorks &quot;Cameras: Film and Photography Basics&quot; . [ONLINE] Available at: http://electronics.howstuffworks.com/camera3.htm . [Accessed 22 February 2012]. </li></ul><ul><li>HowStuffWorks &quot;What are CCD or CMOS image sensors in a digital camera?&quot;. 2012. HowStuffWorks &quot;What are CCD or CMOS image sensors in a digital camera?&quot; . [ONLINE] Available at: http://electronics.howstuffworks.com/cameras-photography/digital/question362.htm . [Accessed 22 February 2012]. </li></ul><ul><li>HowStuffWorks &quot;Photovolatic Cells: Converting Photons to Electrons&quot;. 2012. HowStuffWorks &quot;Photovolatic Cells: Converting Photons to Electrons&quot; . [ONLINE] Available at: http://science.howstuffworks.com/environmental/energy/solar-cell1.htm . [Accessed 22 February 2012]. </li></ul><ul><li>Images </li></ul><ul><li>. 2012. . [ONLINE] Available at: http://www.melbpc.org.au/pcupdate/2303/2303article4-2.jpg . [Accessed 22 February 2012]. </li></ul><ul><li>. 2012. . [ONLINE] Available at: http://static.ddmcdn.com/gif/digital-camera-splitter.jpg . [Accessed 22 February 2012]. </li></ul><ul><li>. 2012. . [ONLINE] Available at: http://www.letsgodigital.org/images/artikelen/55/sony_icx624_ccd_sensor.jpg . [Accessed 22 February 2012]. </li></ul><ul><li>. 2012. . [ONLINE] Available at: http://cpn.canon-europe.com/files/education/infobank/capturing_the_image/cmos.jpg . [Accessed 22 February 2012]. </li></ul>

×