If the knob of the potentiometer is turned anywhere to the right, then the phrase on the LCD screen will become brighter because the resistance value will decrease.

A Liquid Crystal Display (LCD) is a type of output display that uses liquid crystals combined with polarizers. LCDs come in all sorts of shapes and sizes. They are also very flexible depending on their size. They were first invented in 1964 by Radio Corporation of America (RCA) and it was first mass-produced by Epson in 1982. LCDs have replaced the heavy, bulky, and less energy-efficient cathode ray tubes (CRT) displays. More so, CRTs were more prone to break due to them being mostly made out of glass.

There are six layers to an LCD screen:

• The first layer consists of a polarizer filter film that has a vertical axis that allows light that enters through to be polarized
• The second layer consists of a thin glass sheet that contains indium tin oxide (ITO) electrodes. The shape of these electrodes are embedded into the glass sheet, which determines what will be shown when the LCD is switched on
• The third layer has a thin layer liquid crystals arranged in a way called the twisted nematic field effect
• The fourth layer has another thin glass sheet that contains ITO electrodes but this layer has horizontal ridges that lines up with the horizontal polarizer film
• The fifth layer has a another polarizer filter film but this one has a horizontal axis that either blocks or passes light
• The sixth layer consists of a reflective surface that sends light back to the viewer. In a backlit LCD, the reflective surface is replaced by a light source

LCDs use much less power than the bulky CRT, which makes them produce less heat than its predecessor. LCDs produce no image bleeding nor smearing and produce high-quality images when displayed in a fixed resolution. Unlike CRTs, LCDs are not affected by any magnetic interference. LCDs can also display data from a Digital Visual Interface (DVI) or High-Definition Multimedia Interface (HDMI) connection without having the need to convert to analog data. But there can be downsides to having an LCD like limited viewing angles in older, cheaper displays. This is due to the viewer’s position on viewing the display, which affects the color, saturation, contrast, and brightness in certain angles. LCDs have a variety of applications such as TVs, monitors, digital watches, calculators, smartphones, and many more devices that require an output display. 

A potentiometer is a type of resistor that has three-terminal ends with a sliding rotating contact that forms an adjustable potential divider. Potentiometers are mostly used to control electronics for example they are used to control the volume of audio equipment. It can also be used to control the speed of a fan. Potentiometers can also act as a position transducer, a type of mechanism that converts a signal from one type of energy to a signal in another type of energy, which is used in joysticks for example. Potentiometers consists of a resistive element (made from carbon or other highly resistive materials), a sliding contact that makes electrical contact with the element, two of the terminals are attached to the ends of the element and the other terminal is attached to the sliding contact, a shaft that moves the sliding contact from one part to the other and a housing to enclose the element and the wiper. 

A trimpot is a type of potentiometer that is adjustable but it is really small in size. They are commonly used to initially calibrate equipment after the manufacturing process. They are usually mounted directly on a printed circuit board (PCB) due to them having three-terminal legs instead of the ones with holes in the terminals and their knob can be turned by a screwdriver. The name trimpot used to be a registered trademark from a company called Bourns, but later the name became generic. There are two main types of trimpots, a skeleton potentiometer, and a multi-turn potentiometer. A skeleton potentiometer works like a regular trimpot but it’s stripped from its enclosure and shaft. They also move less than a single full turn. A multi-turn potentiometer has a type of gearing arrangement inside the trimpot so it can do multiple turns, which makes it really precise to set the resistance.

A breadboard, sometimes called a solderless breadboard, is an electronic component that is used to build a prototype for an electronic circuit. Unlike other prototype boards that require soldering such as a stripboard, breadboards do not require the use of solder and can be used over and over again. This is a reason why it is really popular among students and people wanting to explore and experiment with electronic components. Inside the breadboard there are rows (or columns) of metal clips made out of phosphor bronze that are plated with tin or nickel silver, which are called tie points. Most of these tie points are located in a terminal strip in a typical breadboard where they are often used to hold down through-hole electronic components and jumper wires. Some breadboards have only terminal strips on them, but others have another type of strip called the bus strip. The bus strips are commonly used to manage power supply and ground for an electronic circuit. Although the main benefit is that it is solderless, there are however a few disadvantages like it cannot accommodate any surface-mount devices (SMDs) and can be really difficult to replicate the actual circuit you want to try out. 

Jumper wires, sometimes called DuPont wires, is a type of electrical wire or cable that has connection points pre-fitted into them. The most common jumper wires are ones that have a solid tip on their ends, which are mainly used in breadboards and other types of prototyping boards. There are also types of connection points such as crocodile clips, banana jacks, registered jacks, radio frequency connections and RCA connections. 

Manipulated variable: The position of the knob on the potentiometer. 

Responding variable: How bright or dim the phrase of the LCD screen is.

Controlled variables: the voltage of the battery, the UNO R3 controller board, and the size of the LCD screen.

1. Connect jumper wires to a Breadboard and to the UNO R3 controller board to configure the LCD and potentiometer so that you can program.
2. Connect the USB cable to to the UNO R3 controller board.
3. Open Arduino coding app.
4. Program the LCD screen so it can start up and show a phrase (you don’t need to program the potentiometer). Like this:

// Import the Liquid Crystal library

#include <LiquidCrystal.h>;

//Initialise the LCD with the arduino. LiquidCrystal(rs, enable, d4, d5, d6, d7)

LiquidCrystal lcd(12, 11, 5, 4, 3, 2);

void setup() {

  // Switch on the LCD screen

  lcd.begin(16, 2);

  // Print these words to my LCD screen

  lcd.print("HELLO IM AN LCD!");

}

void loop() {

  // put your main code here, to run repeatedly:

}

5. Start the program and see if it works, if i doesn’t then take a look at the wires and see were you go wrong.

We analyzed that by turning the knob of the potentiometer to the middle, I saw the phrase disappear. This might be because the potentiometer doesn’t let any electrons go through. Then I turned the knob from the middle to a quarter to the right, the phrase wasn’t too dim nor too bright. This might be because the potentiometer is letting a steady flow of electrons through. Then I turned the knob all the way to the right, this made the phrase so bright you can barely see the phrase. This might be because the potentiometer is letting almost all the electrons go through. This is similar to a floodgate in where we control the flow of something and in this case we control the flow of electrons.

It was predicted in our hypothesis that turning the potentiometer anywhere to the right would make the phrase on the LCD screen brighter. That’s because the potentiometer is like a resistor. There are different types of resistors. Different resistors have different effects but with a potentiometer, it’s a three-way variable resistor that you can control.

LCDs are used in a variety of devices such as watches, cameras, projectors, TVs, monitors, calculators, smartphones, outdoor billboards and it can be even in cockpit displays in commercial airplanes. Potentiometers are also used in a wide variety of devices such as turning a knob to adjust the volume or brightness of a television or it can be used as a tone controller or equalizer in most audio equipment. They are also used in gaming, more specifically in joysticks. Breadboards are mainly used to prototype certain circuits and projects. Jumper wires have a wide variety of applications depending on what type of connection point it has such as being used in telephone and land access network (LAN) connections, being used in prototype and test equipment, transmit audio and video signals and carry and transmit radio frequency signals.

None

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I want to say thank you to Zebulun for doing the slides.