My old camera, Cannon PowerShot A85, stopped working a few days ago. I decided to rip it apart completely, being the curious enginerr I am !
I will take you through the step I will also explain very briefly what the part are. In the coming days I will complete the blog with detailed description of each part and its function. In other words, I will try to reverse engineer the thing to the best of ability in the given time constraints I have.
All the pictures that were taken, were from cannon digital slr , xsi ( I treated myself to it after getting my post-doc position).
First, there are about 5 main parts to a camera.
Battery compartment: Any system needs energy to run, so a camera is powered by batteries. Simple stuff. This is an old camera, was powered by 4 cells. Crazy. This made the camera so heavy, I thought It could easily substitute for a weapon!
Lens: Any camera must be able to “see”. The focus the light rays onto the CCD sensor, thereby enabling the camera to take the photo of the object or the person you want.
Flash: It is made of two main parts one is the Lamp other is a flash capacitor:
The flash lamp is operated by a flash capacitor. Part of the energy supplied by the batteries go into powering the capacitor
Flash capacitor: The capacitor is device that stores electric charge. A large capacitor is needed for your “flash photography” ( low lighting and your picture is no good). In order for the flash to work, a capacitor is used to store enough energy for the bulb so that it can discharge when needed for the flash. The one used here is a cylindrical capacitor. ( For more about capacitor look at wiki or something).
CCD Sensor: I don’t want to go into the details of the CCD sensor. It is a complicated device and the description for the working of the CCD will take a post on its own. For the time being, let me say the CCD -charge couple device- is a light sensor micro-chip that is connected to the lens and it is one that helps catches the light. The number of pixels that you hear is the number of tiny sensors that are present on the catching surface. The larger the number of pixels the better the resolution.
Image processor and auxiliary circuits: The processor is the brain of the digital camera. The processor , with the help of the auxiliary circuits, the CCD sensor signals into digital signals for storage.
Memory: The memory is where the photo is saved. The memory in the camera has usually has a built in device or a slot for a memory card. This camera, power shot A85, has a memory slot.
LED: The small red blinker that is present on the camera for indicating when the self-timer is operating.
USB Port and connector: To enable transfer of the photos to a computer, external storage.
A case to house the components.
Before the Operation…….
1. After removing the top case.
On the left the Black color panel is the display unit. A unit to show the photo usually taken. It is also powered by the battery and controlled by the auxiliary circuits and a display driver.
The metal case to the right of the display panel is the memory card slot. It is supported with the metal case. When we take the support case out….
Looking from the other side at the moment
Now one can see the flash (bottom left bright white rectangular piece), next to it the focal lens for you to see the object, the other lens to catch the object is the large one (I couldn’t find out how to keep the shutter door open mechanically).
The two lenses shown after being taken out of the camera.
The processor with the auxiliary units. The brown strip are small wires called buses, to transfer electrical signals from one unit to another.
The other auxiliary circuits. This part handles the power distribution. The red wire is the main power supply, and the power has to be distributed to several units such as display, ccd sensor, memory etc.
The above shown picture is the large flash capacitor.
Flash Unit with the lamp and the capacitor.
The auxiliary circuit unit for power supply.
In the coming days, I will expand on the post. Till then Enjoy “inside the digital camera”.