Risk Assessment:
According to internet source:
- don’t look directly into a beam of IR light and avoid eye damage by using UV goggles.
Equipment:
- 1 standard TV remote control
- 1 hard cover book (encyclopedia size)
- 1 TV set which corresponds with TV remote
- Ruler with “mm” markings
The following materials: 1 pack of blank paper, 3 sheets of transparent glass (5mm each), metal (copper alloy), slate, Playdoh™, leather samples, folded bed sheet linen, folded 100% cotton towel, wood, ceramic (china), latex rubber, plastic rulers, tissues (serviettes), hard foam (mousemat), packaging foam.
Method:
- Stand at a distance where the receiver can receive signals emitted by a remote control – keep this distance constant.
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Hold the remote at a 90° angle – place it on top of a book or any other flat surface, making sure the surface is flat and not tilted to an angle.
- Using any material with a thickness of 5mm or by tightly compress those materials with several pieces (ensure the thickness is uniform), place it directly in front of the remote’s IR pathway so that the material touches and spans the width of the front of the remote (leave no airspace).
- Aiming the remote at the centre of the TV, press the same button 3 times, with a 5 second break in between.
- Repeat the last 2 steps with as many possible materials, pressing the same button from the same location each time.
- Repeat the experiment using the same materials, doubling the thickness each time. i.e. testing 3 thicknesses: 5, 10 & 20 mm.
Results:
Conclusion:
Of the materials tested, those which are transparent or have a high occupancy of airspace such as glass and foam respectively, are the least effective in blocking off IR signals emitted by the TV remote. In contrast, those which are most effective for this purpose are wood, metal, paper, cotton towel and leather.
Discussion:
My first attempt at this experiment failed because, originally, I had proposed to leave a 5cm gap between the material and the emission part of the remote. This didn’t work as none of the materials were blocked. So, upon making the necessary modifications, the experiment was successfully executed.
Having said this, my experiment was successful because I made use of repetition to ensure the reliability and validity of my results. I have also compared my results to those of others through browsing the internet. Since others had obtained similar results – that transparent materials and those with a high occupancy of airspace are least effective in blocking off signals by a TV remote – I have proved that my results are reliable. By using an appropriate measuring device, a ruler with “mm” markings, I have also justified the accuracy of my results.
Although this experiment was a success in that I correctly tested my aim and hypothesis to deliver the expected result, there would still be elements of design which can be improved. If I performed this experiment again, I would ensure that the remote be placed directly from the centre of the TV, not just any location. This would ensure a clearer signal, resulting in more accurate results and contributing to the experiment’s overall efficiency. Also, the width of the material is irrelevant to the experiment and does not need to be controlled. Furthermore, the remote should be placed on a stationary surface e.g. coffee table, instead of balancing a book on one hand. This would avoid tilt by encouraging a level surface, which could possibly affect the accuracy of the results. Another aspect would include taping together any loose material instead of compressing them with my fingers. I believe these factors had led to minor flaws in the accuracy and reliability of my results.
