A brief guide: choosing display technologies for your project
Display technologies come in all shapes and sizes from small LCD, OLED and TFT for displaying basic letters through to large TFT displays suitable for streaming. This piece from Ignys discusses some core considerations that designers must make to ensure that the correct monitors are utilised.
What you choose should always be customised to your application and how you want to interface to your customer.
The environment you plan to use your display in plays a huge role in your technology choices.
For example, outside use requires high bright backlights, for touchscreen you may want to optically bond this to the display to compensate for sunlight and optimise user comfort and UX.
High and low temperatures need checking too, this is an important factor for electronic design in general where environmental simulation testing comes in useful.
For industrial settings the user may need PPE such as gloves and there may be water droplets present on the screen, this means IP ratings need to be taken into account.
People can act in an unpredictable way, particularly in public areas, you need to account for worst case scenarios such as violence which could result in damage to the screen or someone being injured.
Thicker glass is a way to add protection and special coatings can stop a screen shattering in a dangerous way.
What is your end goal?
Product development has the power to make the world a better place but if you don’t plan for the right margins, you’ll be unable to invest in future products. This means helping less people in the long run. So, making sure you get the right Return On Investment (ROI) is hugely important.
Equally, is your product going to be useful to enough people? Make sure the price you plan to sell your product at doesn’t put customers off and understand the size of your target audience and their buying patterns.
Look at the longevity of your project carefully so you and your customers get the most out of your plans.
Getting the electronics design side right
Integrating display technologies can vary depending on how much electronics design you plan to do in-house and your use of components.
Steven Richardson, Senior Electronics Engineer from Ignys explains: “For example, does your display require a fast digital interface like MIPI, low speed serial (SPI, I2C) or parallel[HI1] (24-bit RGB).
These factors determine how much processing power you are going to need and if you will require a microprocessor with an integrated display controller or just a simple microcontroller.
Also consider your update refresh rate, do you really need high refresh rates for showy animation? If you are just displaying figures and a nice UI, then slower refresh rates will make your electronics simpler. Animation, transparencies and effects will increase your processing requirements adding more power and cost.”
If time to market and development costs matter strongly to you there are several intelligent display options that allow you to easily design the user interface through a graphics chip using some pre-defined software. This allows you to concentrate on other design areas.
You can also save time on a project by using an expert design consultancy rather than trying to do it all yourself. Software is an important factor too, bad code can derail a project. Make sure you plan ahead.
Not long ago touchscreens were revolutionary, now they are a major part of life. People now expect to see displays and interactive screens from cars to check-outs, this is creeping in more in industrial settings too with either resistive or capacitive touch.
As with many technologies the more it advances the cheaper it is to use and implement, making these options far more viable. However, this doesn’t mean you should jump on the touchscreen bandwagon if physical buttons make more sense to your application, take a step back and do some valuable customer research.
Key challenges with display technologies
Exploring the problems product developers come across.
Rushing the specification
The internet is not always your friend when it comes to writing a good specification. The choice of displays is so vast that it’s easy to waste many hours of research and make costly decisions to lead to added expenses, poor usability, and project delays, none of which you can afford.
One of the costliest mistakes you can make with displays is not checking your parts have longevity of supply, for industrial applications certification can take years, if you then find out parts have gone to their end-of-life stage this can have huge ramifications.
Aim for 5+ years to avoid disaster. Develop close relationships with your suppliers.
Global chip shortages are not something to be underestimated, many have chosen not to take this seriously and by the time they realise the extent of lead times it’s too late.
In addition, chips cost a lot more than they used to. Talk about components early and get supplies booked in and avoid any components which only have a single source. Don’t rely on being able to get the parts later in the design stage.
Consider how you want the customer to interface with the application.
Low power design
This is a major talking point in the electronics industry. Consider how much power your product needs out in the field and look at battery capacity.
You need to look at battery power applications and how you will recharge the battery, you don’t want to increase truck rolls to change batteries, this is bad for your team’s time and money, and it has environmental consequences.
Some applications don’t require a lot of power such as Kindle-style ePaper technology.
Not getting the right support
The earlier you get the right support from both the display and electronics perspective the less costly mistakes you’ll incur later.
Getting support from the concept stage allows both parties to understand what you’re looking to achieve, design for availability and avoid wasting time.
Taking these valuable factors into consideration will help you plan your project and get the most out of your display technologies.