Arduino-compatible projects can use many different display types. Character LCDs, OLED displays, TFT color displays and ePaper displays are all common choices, but they are designed for very different use cases.
This article compares these display types from a practical project point of view. The goal is to help choose a display based on readability, power consumption, size, color, update speed, wiring and software complexity.
Four Common Display Types
Each display type has a clear personality. Some are simple and reliable. Some are bright and compact. Some are colorful. Some are extremely low power when the image does not change often.
- Character LCD: simple text display, commonly 1602, 2004 or similar formats
- OLED: small high-contrast graphic display, often monochrome
- TFT LCD: color graphic display for menus, icons, images and user interfaces
- ePaper: paper-like display that keeps the image without continuous power
The best choice depends on what the project needs to show and how often the display content changes.
Character LCD: Simple Text Display
Character LCD modules are classic Arduino displays. Common versions include 16x2, 20x4 and 16x4 character formats. They are designed to show text, numbers and simple symbols rather than graphics.
- Simple and reliable
- Easy to read for text and numbers
- Available with parallel or I2C backpacks
- Good for menus, measurements and status displays
- Limited to fixed character positions
- Usually not suitable for graphics or images
A character LCD is a good choice when the project only needs to show clear text such as temperature, voltage, time, menu options or system status.
OLED: High Contrast in a Small Size
OLED displays are popular because they are compact, sharp and high contrast. Many Arduino projects use small monochrome OLED displays such as 0.91", 0.96" or 1.3" modules with I2C or SPI interfaces.
- Very high contrast
- No backlight required
- Good viewing angle
- Useful for small graphics and icons
- Commonly available with I2C interface
- Limited size on many low-cost modules
OLED displays are excellent for compact projects, small instruments, sensor readouts, portable devices and projects where a sharp small display is needed.
TFT LCD: Color Graphics and User Interfaces
TFT LCD displays are used when a project needs color, larger graphics or a more advanced user interface. They are common in sizes from small 1.8" modules to larger 2.8", 3.5" or even bigger displays.
- Color display
- Good for graphics, icons and menus
- Available in many sizes and resolutions
- Often uses SPI or parallel interface
- Requires more memory and processing than character LCDs
- Backlight consumes power continuously while on
TFT displays are the right choice when the project needs a real graphical interface, color status indicators, charts, images or touchscreen-style menus.
ePaper: Paper-Like Display With Image Retention
ePaper displays are very different from LCD and OLED displays. They are reflective, readable in ambient light and can keep an image visible without continuous power.
- Image remains visible without constant refresh power
- Excellent readability in bright ambient light
- Very low power for infrequently changing displays
- Good for labels, clocks, price tags and information panels
- Slow refresh compared with LCD or OLED
- Usually not suitable for fast animation
ePaper is best when the displayed information changes occasionally, not many times per second.
Main Comparison Table
| Feature | Character LCD | OLED | TFT LCD | ePaper |
|---|---|---|---|---|
| Best for | Text, numbers and simple menus | Small sharp graphics and compact status displays | Color graphics and user interfaces | Static or slowly changing information |
| Color | Usually monochrome characters with backlight color | Usually monochrome on common modules; color versions exist | Full color on most modules | Usually black/white, sometimes red or yellow accent colors |
| Graphics | Very limited custom characters | Good for small graphics | Very good | Good for static graphics |
| Update speed | Good for text updates | Fast enough for most small displays | Good, depends on interface and library | Slow compared with LCD/OLED/TFT |
| Power use | Backlight can dominate power consumption | Depends on number of lit pixels | Backlight usually consumes continuous power | Very low when image changes infrequently |
| Readability in sunlight | Depends on LCD type and backlight | Can be difficult in strong sunlight | Depends strongly on brightness and display type | Excellent in ambient light |
| Typical interface | Parallel or I2C backpack | I2C or SPI | SPI or parallel | Usually SPI |
| Software complexity | Low | Medium | Medium to high | Medium, with refresh behavior to consider |
Text vs Graphics
The first question is whether the project needs text only or graphics.
- Use a character LCD for simple text and numbers
- Use OLED for small icons, compact graphics and sharp readouts
- Use TFT for color graphics, menus and images
- Use ePaper for static graphics, labels and information screens
If the project only displays “Temperature: 23.4°C,” a TFT display may be unnecessary. If the project needs a graphical menu, a character LCD may be too limited.
Power Consumption
Power consumption can be a deciding factor, especially for battery-powered projects.
Character LCDs and TFT displays often use backlights, and the backlight may consume more power than the display controller. OLED power depends on how many pixels are lit. ePaper can be extremely efficient when the image changes only occasionally.
| Power Situation | Best Display Direction | Reason |
|---|---|---|
| Battery device with rarely changing display | ePaper | Image remains visible without continuous display power |
| Small low-power status display | OLED or low-power LCD | Compact and readable, but content and brightness matter |
| Bench-powered device | Any display type | Power consumption is less critical |
| Always-on color interface | TFT LCD | Color and graphics are more important than lowest power |
Update Speed
Update speed is another major difference.
- Character LCDs are fine for occasional text changes
- OLED displays can update quickly enough for many small graphical interfaces
- TFT displays can handle color graphics and responsive menus
- ePaper displays refresh slowly and are not meant for fast animation
For a clock with seconds, OLED or LCD is usually better than ePaper. For a price tag, label or status panel that changes a few times per day, ePaper is excellent.
Readability and Viewing Conditions
Display readability depends on lighting conditions.
- OLED has excellent contrast indoors
- TFT can look great indoors but may need strong backlight outdoors
- Character LCD readability depends on LCD type, contrast and backlight
- ePaper is excellent in bright ambient light because it is reflective
If the display must be readable outdoors in sunlight, ePaper is often the strongest choice. If the display is used indoors in a small instrument, OLED can look very sharp.
Microcontroller Memory Requirements
Graphical displays usually require more memory and processing than character LCDs. This matters when using small microcontrollers such as ATmega328P-based Arduino UNO or Nano boards.
- Character LCDs require very little memory
- Small OLED displays are manageable on many Arduino boards, but full display buffers can use significant RAM
- TFT displays often benefit from faster 32-bit controllers
- ePaper displays may require careful library and buffer choices on small microcontrollers
For larger graphical displays, boards such as ESP32, RP2040, RP2350 or STM32 are often more comfortable than classic 8-bit Arduino boards.
Interface and Wiring
Wiring complexity depends on the display module.
| Display Type | Common Interface | Practical Notes |
|---|---|---|
| Character LCD | Parallel or I2C backpack | I2C backpack greatly reduces wiring |
| OLED | I2C or SPI | I2C versions are very convenient for small projects |
| TFT LCD | SPI or parallel | SPI uses fewer pins; parallel can be faster but needs more pins |
| ePaper | Usually SPI | Additional control pins are often required |
Voltage Compatibility
Many modern displays use 3.3V logic. Some modules include level shifting or regulators, but this should not be assumed.
- Check whether the display module is 3.3V or 5V compatible
- Use level shifting when connecting 5V Arduino boards to 3.3V displays
- Do not assume an I2C display is automatically 5V safe
- Check backlight power requirements on LCD and TFT modules
Voltage compatibility is especially important when connecting displays to Arduino UNO, Nano, ESP32, RP2040 or XIAO boards.
Character LCD Advantages
- Simple text display
- Low software complexity
- Good for measurements and menus
- Widely supported by Arduino libraries
- I2C backpack versions reduce wiring
Character LCDs are still very useful when the project only needs readable text.
OLED Advantages
- Very sharp and high contrast
- Compact size
- Good for small graphics
- No backlight needed
- Common I2C versions are easy to wire
OLED displays are excellent for compact devices and small instruments.
TFT LCD Advantages
- Full-color graphics
- Useful for icons, menus and images
- Available in many sizes
- Good for richer user interfaces
- Some modules include touch input
TFT displays are the right choice when a project needs a real graphical interface.
ePaper Advantages
- Very low power for static information
- Readable in bright ambient light
- Image remains visible without continuous power
- Paper-like appearance
- Good for labels and slow-changing displays
ePaper is excellent for information that does not change often.
Which Display Should You Choose?
| Project Need | Best Choice | Reason |
|---|---|---|
| Simple text and numbers | Character LCD | Easy, readable and low software complexity |
| Small sharp status display | OLED | High contrast and compact size |
| Color menu or graphical interface | TFT LCD | Supports color graphics and richer UI design |
| Battery-powered label or static display | ePaper | Image remains visible with little or no continuous power |
| Outdoor-readable static information | ePaper | Reflective display is very readable in ambient light |
| Fast-changing values or animation | OLED or TFT LCD | Much faster refresh than ePaper |
| Classic Arduino beginner menu | Character LCD | Simple and well supported |
Common Mistakes
- Choosing ePaper for fast-changing data or animation
- Choosing a TFT display for a project that only needs two lines of text
- Ignoring display memory requirements on small Arduino boards
- Assuming every display module is 5V compatible
- Forgetting that LCD and TFT backlights can consume significant power
- Using a display that is too small for the viewing distance
When to Use Something Else
Sometimes a display is not the best user interface.
- Use LEDs or a 7-segment display for simple status or numbers
- Use a web interface when the device already has WiFi
- Use serial output during development instead of adding a display too early
- Use a larger HMI display when the project needs a full touch interface
Conclusion
Character LCDs, OLED displays, TFT LCDs and ePaper displays all have useful roles in Arduino-compatible projects.
- Choose a character LCD for simple text, numbers and menus.
- Choose an OLED for compact high-contrast graphics and status displays.
- Choose a TFT LCD for color graphics, icons and user interfaces.
- Choose ePaper for low-power static information and excellent ambient-light readability.
The best display is the one that matches the information being shown, the viewing distance, the power budget and the update speed required by the project.