Think About It Thursday: How Does A Polaroid Camera Work?

Today, May 7, is the birthday of scientist and inventor Edwin H. Land. Land was born on May 7, 1909 and is known mostly for his inventing of the Polaroid instant camera.  Happy Birthday Mr. Land!! Land also co-founded the Polaroid Corporation in 1937. Among other things, Land invented inexpensive filters for polarizing light, a practical system of in-camera instant photography. His Polaroid instant camera, which went on sale in late 1948, made it possible for a picture to be taken and developed in 60 seconds or less.

The trick to the Polaroid camera is in the film itself. The film contains three silver compounds. When these compounds are exposed to a large number of light photons, it forms silver atoms. In the color film typically used with the Polaroid camera, the top layer is sensitive to blue light, the next layer is sensitive to green and the bottom layer is sensitive to red. When the film was exposed, the sensitive grains at each layer react to light of that color, creating a chemical record of the light and color pattern. Underneath each color layer, there is a developer layer containing dye couplers. All of these layers sit on top of a black base layer, and underneath the image layer, the timing layer and the acid layer. This arrangement is a chemical chain reaction waiting to be set in motion.

Check out this video below to see exactly how a Polaroid camera works!

 

The Tech Behind the XBOX 360 Kinect- Is it Science or Magic? *Hint- It’s Science!*

 

The new XBOX 360 Kinect is a game-changer when it comes to how we play our games. At first glance, Kinect looks like an overly wide webcam and indeed an RGB camera is one of its components. What sets Kinect apart is that it also incorporates a depth sensor and multi-directional microphone array to create a plethora of additional features and functionality. Where a camera can merely track movements in two dimensional space, Kinect can track movement in three dimensions and perform facial and voice recognition. Furthermore, Kinect connects to its base on a motorized pivot which allows for a certain degree of movement

The two stars of the show are the depth sensor and RGB camera. While we all might have an idea of how an ordinary camera works, the idea of a depth sensor is definitely out of the ordinary. The way the depth sensor works is by firing an infrared laser into the room and subsequently using an image sensor to gather information upon the reflection of the infrared beams. Data, including the amount of light reflected back as well as the time it takes the laser to return to Kinect, is compiled to compose a 3D map of the room. It’s very similar to a bat’s use of echolocation in navigating the environment despite having poor eyesight

When the depth sensor and RGB camera work together it allows Kinect to track up to six people passively and two people for actual motion analysis. In simpler terms it means that while it may be able to recognize six people at once it’s really only designed for two people to be playing games through it. When Kinect monitors two people and performs its motion analysis, it’s able to extract detailed information including recognition of up to 20 joints for each player right down to individual fingers in certain instances.

For more on the X-BOX Kinect- check out these stories online:

http://www.msnbc.msn.com/id/40077373/ns/technology_and_science-games/

http://www.microsoft.com/presspass/features/2010/nov10/11-03kinect.mspx

http://www.npr.org/2010/11/19/131447076/how-the-x-box-kinect-tracks-your-moves