Ray tracing Essays

Ray tracing Essays Ray tracing Essay Ray tracing Essay The objective of this experiment is to find the length of an object and its focal lengths. I will first try to hypothesize where the length points will be. The given results of my hypothesized diagrams will determine the lengths of the focal points. I will then be able to find out where the object image will be situated by following my ray trace diagrams. I believe that I will be able to find the length of the object image if I can find the two focal length points ( 1/v and 1/u displayed in my ray trace diagrams and the focal graph). To achieve this I have decided that I could not get an accurate hypothesis if I did not know this information, so I will carry out a small practical experiment. We found that if the lens is thin, the focal length is longer, and if it is thicker, the focal length is smaller. The focal length for our lens is 10cm. I have created some ray tracing diagrams to show my predicted lengths using the focal length that I found. I have found the longest distance that I can get a clear image is 100cm, the shortest being 15cm. I then carried out an experiment to prove my hypothesis. I used light boxes to create a light source, but this is not extremely accurate as the light rays diverge and are not parallel. I used a screen and a lens to try to find an image. My results for my experiment were as follows. I had three atempts to make my experiment more accurate. Image lens Lens Screen Image size (cm) 1st/2nd/3rd attempt (cm) 1st/2nd/3rd attempt (mm) 15 33/35/36.5 25/28/29 25 18/18/18.5 9/9/9 40 15/14/15 5/5/4 50 14/13.5/13.5 3/3/3.5 60 13.5/13/13.5 2.5/2.5/2.5 80 12.5/12.5/12.5 1/1/1.5 100 12/12/12.5 1/1/1 I have found the averages of the 3 attempts and have also put these in a table. Image lens Lens Screen Image size (cm) Average(to 2dp, cm) Average (to 1dp, mm) 15 34.80 27.3 25 18.17 9 40 14.67 4.7 50 13.67 3.2 60 13.33 2.5 80 12.50 1.3 100 12.17 1 This data is represented in a graph. It shows that the longer you move the object to the lens away, the less distance between the screen to the lens is needed to get a clear image. The further the object to the lens is the smaller the image size. The only problems that I had with my experiment were the fact that the light rays were not perfectly parallel. This could of lead to the rays moving away from the focal points, and could then move the object image a few millimeters, which could change the results by a lot. The other problem was the materials. These were not of a high quality, and the measuring devices we used were 1 meter rulers, which were not accurate enough to the millimeter. We also did not know what thickness the lenses were, so we could not go into further detail into the changes, which they may have caused. Overall the experiment was a success. It showed basically what my raytracing diagrams, and my hypothesis had shown. It gave a clear, precise trend on how the lengths change. Changing with size it shows the further you pull the object from the lens, the shorter length you have to put the lens from the screen.