Team:USTC/Tutorials
Thank you for using the SPRING, a fast optical interference detecting device.
Before you using SPRING, please carefully read this instruction manual to fully understand the operations and the attentions.
Materials
To accomplish SPRING, you need prepare those material showed below:
| Materials | Number | Price in estimation($) |
|---|---|---|
| 12 in 1 display | 1 | 92.08 |
| CSI Interface Camera | 1 | 13.88 |
| Camera Bracket | 1 | 1.42 |
| 3V laser head | 2 | 0.31 |
| 5V laser head module | 2 | 1.73 |
| Arduino UNO R3 | 1 | 4.67 |
| Universal circuit board | 5 | 0.41 |
| Breadboard | 2 | 1.75 |
| Dupont line | 15 | 4.25 |
| 12V lithium battery | 1 | 15.72 |
| 12.6V 3A Chargers | 1 | 6.06 |
| DC-DC step-down module | 2 | 5.04 |
| PP board | 1 | 7.71 |
| Miniature hand drill | 1 | 20.46 |
Protection Guide
When you are making NDM, many tools are needed, as well as touching bacteria solution. Consequently, we provided four recommended protective measures for everyone. Please pay attention to personal safety when doing experiment:
- Level A: Fundamental protective measure when producing NDM and conducting experiment. You may wear lab coat. When conducting experiments and assemble NDM, level A should be satisfied always.
- Level B: In level B, personnel should not only wear lab coat, but wear nitrile gloves or latex gloves, which are necessary when touching bacteria solution. This procedure is the first step for detection.
- Level C: Level C is the standard protocol for personnels when drilling. In addtion to level A, you should wear goggles. Goggles would protect your eyes when you are drilling plexiglass. And please do remember ROLL UP YOUR SLEEVES to prevent possible hurts and DO NOT WEAR GLOVES because it is not convenient when drilling.
- Level D: This is the most complicated protective measure for spraing painting procedure. One should wear lab coats, along with goggles, masks and gloves to toally protect oneself considering extreme pungent odor volatilizing when painting.
Tools
- Drill is used for cutting acrylic materials for assemble bracket.
- Electric soldering iron, for welding electric circuit.
- Glue gun is needed for adhesion between each other acrylic materials.
Display module
The display module contains 12 in 1 display with processor and buttons. Users are able to control the power, contrast and other display effects through buttons beside the display.
Raspberry Pi
Raspberry Pi, is the main hardware module that can take photos or videos of interference fringes, then our software analyses them or transmits to your PC. we can see the results on the screen.
Circuit Elements
- Transformer: The responsibility of transformer is to drop voltage 12V produced by lithium battery to 5V, which is needed to supply cooling fan on Raspberry Pi and laser beam.
- Breadboard: Many solderlessly electronic circuits tests will be conducted on breadboard.
- Lithium-polymer battery: Provide power, 12V, 10000mA·h.
Optical Path Elements
The schematic figure of optical path is based on Michelson interferometer, to get more principle of optical path in SPRING, please refer to: Project-SPRING
Here we will introduce elements that are indispensable for interference patterns formation.
- Webcam, containing CCD(charge-coupled device) image sensor, is able to capture picture, mainly for interference pattern capture.
- Laser, wavelength: 650nm, 5V power supply
- Expander is to expand the diameter of the laser beam. Two reasons are required to expand beam diameter. On the one hand, a larger diameter of the laser beam could avoid laser focusing on detecting film, preventing the possibility of film burned. On the other hand, laser beam would cover the film for better detection.
- Beamsplitter combination, consists of three mirrors, a 50% reflection - 50% transmission beamsplitter(50%(R)/50%(T) in brief), a 80% reflection - 20% transmission beamsplitter(80%(R)/20%(T) in brief) and a 10% reflection- 90% transmission beamsplitter(10%(R)/90%(T) in brief). 1)50%(R)/50%(T) is in the front of picture. The reflection light will project to detecting film , while the transmission beamsplitter will continue going to reflection mirror. 2) Then why do we need The 80%(R)/20%(T), along with 10%(R)/90%(T)? Actually these combination is really important to decrease the relatively high intensity reflected from reflector. Much higher intensity from reflector will not fit the formation condition of interference pattern. 80%(R)/20%(T)+10%(R)/90%(T), approximately allowing 18% light approach reflector, are combined together on the bottom of the picture.
- Reflector, a necessary element for interference pattern formation.
- Sample trough with film, interacting with reflector to form interference ring.
Sample Trough
40X40X40 sample trough
Film Preparation
To see more about our ways to find final film through candidate, please refer to Modeling-Film Candidate.
Our film will be prepared in several processes illustrated below: