Loading Icon
Loading Icon
Share via QR Code
Sharing QR Code

Copy the link below or use the menu on your browser to share.

Dark Mode:
A Level international exam / assessment is in progress. Ken's Study Journey hopes you can pass the exam and get outstanding results!

How can an OLED Screen Take Advantage of our Phones and Computers?

Language/语言:   English   简体中文
Dark Mode:

By: Ken Deng   Published on Sep. 20, 2021

Approx. 1300 words, 6 mins

  Table of Contents

Hello there! My name is Ken and I am a Chinese senior high A Level student in Guangdong Country Garden School. Welcome to Ken's Study Journey website with Computer Science knowledge explanations!

Recently, iPhone 13 and Apple Watch 7 were released. Both of them are using OLED screen display, which is a new technology that can make the screens thinner.

OLED screen was implemented as early as iPhone X, which takes advantage of Apple products. This kind of technology is used on not only phones and watches, but also some TV screens and other screens.

It can be bent to any shape and it is much thinner than the previous LCD (CCFL and LED backlighting) technology, giving people a wide angle of view when watching some virtual reality things.

Do you know why OLED can bring many benefits to Apple devices, and some technical reasons behind it? Let's go!

What is OLED Screen?

OLED screen is shorted by Organic Light Emitting Diode. It is a new technology that uses organic materials such as carbon (C) compounds, and plastics layers.

Related Knowledge

Now, I am going to tell you a relevant IGCSE chemistry knowledge: Polymers.

Plastics is made by polymers, which joins hundreds of small molecules (monomers) together, breaking C=C double bonds in alkenes (CnH2n). This process is called Polymerisation.

If no other substances are formed, it is addition polymerisation. However, condensation polymersation can form other substances to make polyamides and polyesters.

LCD and OLED screens are covered in IGCSE Computer Science (0478) syllabus, so I have fully learned this kinds of knowledge.

OLED does not require backlighting and it can be lit by itself with 2 electrodes around (anode and cathode), so it uses less power and it can be much thinner.

iPhone X uses OLED screen.

iPhone X uses OLED Screen

Types of Screen

There are two types of screens on our phones and computers: LCD and OLED.


LCD is shorted by Liquid Crystal Display, which has 2 separate types: older CCFL and newer LED.

There are thousands of pixels (e.g. 1920x1080) on the screen made by RGB (Red, Green and Blue). It requires backlighting so there is a white light behind, being filtered by the RGB colours.


The first type is the older CCFL, which is shorted by Cold Cathode Fluorescent Lamp.

It uses fluorescent tubes behind the screens, which may turn yellow as it has a limited lifespan (approximately 5 years). Also, it may be very thick, like old computer screens.


To overcome these two problems, LED was developed and it takes advantage of screen display.

LED is shorted by Light Emitting Diode, which uses small white LED lights at the back.

It has the following benefits than CCFL:

  1. It reaches its maximum brightness almost immediately because the lights behind do not need to warm up for a long time.
  2. It is much thinner because the LED lights behind are much smaller.
  3. It has a long lifespan, which does not turn yellow after several years.
  4. Its light is more bright and white, so the images on the display can be more vivid.
  5. It consumes less power than CCFL so it produces less heat with less energy.
Related Knowledge

Now, I am going to tell you a physics knowledge: Energy transfer.

Energy cannot be destroyed or generated, which can only transfer to another type of energy or to another substance.

Electronic devices always produce heat as they consume electricity because there is resistance in the electricity flow. For example, lights always produce heat as well as light energy. The electric energy is transferred to light and heat energy,

The heat energy can be described as wasted energy while the light energy can be described as useful energy because we do not need to use its heat while its light is needed. We can calculate the energy efficiency using (useful energy / total energy * 100%).


Another type of screen is OLED, which has a lot of benefits than LCD and LED.

  1. It is a self-contained system which does not require backlighting.
  2. It uses less power than LCD screens.
  3. It is thinner and lighter.
  4. It uses plastics, so it can be made into thin and large sheets.
  5. It has larger angles (about 170 degrees).
Related Knowledge

Now, I would like to share a mathematics knowledge: trigonometry.

There are 3 functions in trigonometry: sin, cos (cosine), and tan (tangent), along with other 3 extended functions: cot (cotangent), sec (secant) and cosec (cosecant).

Tangent is usually used to calculate gradients of a slope, while sin and cos involve hypotenuse.

We may be difficult to measure the angles of our view because the area is quite large, but we can measure some lengths and calculate the degree of the view.

We can measure the distances between 2 sides of the TV, between the centre of the TV and our seat centre, and between one edge of the TV and our seat centre. Then, calculate the half angle using sin-1, cos-1 or tan-1 functions, and multiply 2 for the whole angle.

View Degree of OLED Screen

Extra Knowledge: Touchscreens

This are the knowledge about OLED screens on the new iPhone and Apple Watch. By the way, I also want to talk about touchscreens, which is relevant to screens.

There are 3 types of touchscreens, capacitive, infra-red and resistive.


Capacitive is the most common type of touchscreen on phones and iPad.

It uses many layers like a capacitor that stores electricity charges. When we touch the top layer of the screen, the charge at the corresponding place is transferred to our hands. Then, the coordinate is determined by the on-board microprocessor.

Because it uses electricity, we cannot touch the screen with gloves because the glove is an insulator while our fingers are conductors.


Another type of touchscreen is infra-red.

It uses infra-red emitters and receivers at the edges of the screen, forming a grid of infra-red signals around it.

When we touch the top layer of the screen, some infra-red signals are stopped by our fingers so the receivers at the corresponding positions cannot receive the signal and hence the coordinates are determined.

It allows touching using gloves because the infra-red signal can be interrupted by any opaque solids. By the way, we can touch the infra-red screens using insulators such as pens.

Because it is an expensive technology, while capacitive is a medium-cost technology, it is not commonly used for screens on major devices.


The last type of touchscreen is resistive.

It uses 2 layers that conduct electricity. The top layer uses plastics and the bottom layer uses glass.

Normally, these two layers are separate. When we touch the top layer, 2 layers form a complete circuit so the coordinate is determined.

Albeit it is a relatively cheaper technology, it has many disadvantages compared with capacitive and infra-red:

  1. It does not permit multi-touch (i.e. touching the screens using many fingers at the same time) because the middle part between 2 fingers is also pressed when we touch it using 2 fingers, so the coordinates can't be determined accurately.
  2. The screen visibility can be poor in strong sunlight.
  3. It can be broken easily if it experiences scratches.

Determining the Type of Touchscreens

We can use several ways to determine the type of touchscreens.

Firstly, if we need some pressure to touch the screen, it is probably resistive because we need some force to press the top layer to the bottom.

Then, we can use some insulators, such as pens and gloves, to touch the screen. If it works, it is probably infra-red. Otherwise, it may be capacitive.


OLED takes advantage of screens on phones and computers because it is much thinner and brighter than LED and CCFL.

Alright! This is the end of the computer science knowledge explanation of OLED screens on iPhone 13 and Apple Watch 7. Thanks for reading and I hope you can understand the computer science knowledge behind on new Apple products.

If you like this explanation, please click the thumb up button below and share this article. Also, you can write down your comment below if you have any ideas. I am a student so my knowledge explanations may contain errors. If it has any errors, you can contact me to correct them.

Still have questions or cannot understand my knowledge explanations? Don't be hesitant to contact me and I am here to help you. I speak English and Chinese.

Subscribe to my email newsletter to receive my latest articles, latest news, latest study tips and tutorials, some useful knowledge in real life, and more!

Is this Article Helpful?

Loading Icon

Pin this on Pinterest

Post Thumbnail

Share this Article

Comments (0)

Privacy Notice: You will receive an email when your comment is replied. I will never disclose your email address. By sending a comment, you agree with my Privacy Policy.

Tip: Always keep your comments positive to motivate other students. You can ask me questions about my articles. Speak politely if you discover any problems or necessary improvements.