What's the Difference Between LCD and OLED Screens?

According to reports, Apple plans to completely eliminate LCD (liquid crystal display) screens across all of its iPhone models, fully transitioning to OLED (organic light-emitting diode) screens. Since the launch of the iPhone X in 2017, which was the first to feature an OLED display, Apple has been expanding this technology to its high-end models.

Advances in display technology have brought increasingly sophisticated visual experiences to our everyday devices. OLED and LCD are currently the two mainstream screen technologies used in common devices such as smartphones, TVs, and tablets. Although they appear similar, the technology behind them and their display performance differ significantly. So, what are the differences between OLED and LCD screens? And how do devices like smartphones and TVs with these screens compare?

Catalog

I. Differences in Technology

II. Differences in Display Performance

III. Which is Better for Your Eyes: OLED or LCD?

IV. Screen Thickness and Flexibility

V. Power Consumption

VI. Screen Lifespan and Burn-In Issues

VII. Price and Popularity

VIII. Application Analysis

IX. LCD vs. OLED Screen Comparison

X. Eye Care Screen Selection Guide

I. Differences in Technology

OLED (Organic Light-Emitting Diode): OLED is a self-lighting display technology based on organic materials. Each pixel emits light independently without the need for an external light source. The OLED screen is made up of multiple layers of organic materials that emit light when electricity passes through them, forming an image. Because there's no need for a backlight, OLED pixels can be individually controlled for brightness, and even completely turned off to display true blacks.

LCD (Liquid Crystal Display): LCD screens rely on a backlight source. Liquid crystal materials themselves do not emit light; they control the passage of light by altering the alignment of liquid crystal molecules, thus forming an image. The liquid crystal layer is sandwiched between two polarized filters, and the backlight is usually provided by LED lights. The light passing through the liquid crystal pixels is adjusted to create different colors and brightness levels.

II. Differences in Display Performance

1. Contrast and black performance：

OLED: Because each pixel can turn off independently, OLED can produce perfectly pure black, resulting in an extremely high contrast ratio. Whether in bright scenes or dark environments, OLED screens excel at displaying true blacks, providing deeper and more realistic images.

LCD: LCDs, dependent on backlight, still emit a faint light even when displaying black, making black appear somewhat grayish. LCDs generally have lower contrast, especially in dark scenes, and blacks are not as deep as on OLED screens.

2. Color Performance:

OLED: OLED offers higher color saturation, displaying more vivid and rich colors. Its self-lighting property allows for vibrant colors in various lighting conditions, making it ideal for multimedia content like movies and gaming.

LCD: LCD also delivers good color accuracy, especially in high-end models, but overall its color performance is slightly inferior to OLED. The color saturation and brightness in LCD are generally more muted, as the colors are limited by the uniformity of the backlight and the optical properties of the liquid crystal layer.

III. Which is Better for Your Eyes: OLED or LCD?

1. Blue Light Issue:

Both OLED and LCD screens emit blue light, which can be harmful to the eyes. However, because OLED screens are self-illuminated, they emit more concentrated blue light, which can be more stimulating to the eyes, especially in low-light environments. On the other hand, LCD screens rely on a backlight, so their light is more evenly distributed, causing less eye strain in dimly lit conditions.

2. Flicker Issue:

OLED screens often use PWM (Pulse Width Modulation) dimming to adjust brightness by rapidly turning the light on and off. While this flickering is generally undetectable to the human eye in normal use, it can cause eye strain, visual discomfort, and even headaches, particularly at low frequencies in dark environments. This effect can be especially bothersome for users who use their phones at night.

In contrast, LCD screens use a different dimming technique, and flickering is much less of an issue. While earlier LCD models did exhibit flickering, improvements in technology have led to the widespread adoption of "flicker-free" technology, reducing eye strain.

Overall, LCD screens tend to be gentler on the eyes in terms of blue light and flicker, making them more suitable for long-term use, especially for users who spend extended periods on their devices.

IV. Screen Thickness and Flexibility

OLED: OLED screens are incredibly thin, even flexible, since they don’t require a backlight. This makes OLED ideal for curved, foldable, and innovative designs. Devices like smartphones and smartwatches can take advantage of OLED's thinness to create sleek, borderless, or foldable displays.

LCD: The structure of an LCD screen is more complex, requiring a backlight, polarizing filters, and a liquid crystal layer. As a result, LCD screens tend to be thicker and cannot be as flexible as OLED screens. While some LCD screens can be made thin, they lack the flexibility of OLED.

V. Power Consumption

OLED: OLED screens consume significantly less power when displaying dark images because the pixels can be turned off or dimmed. This means that if you use dark themes or watch dark scenes, OLED screens will consume less battery, especially when displaying pure black.

LCD: LCD screens require the backlight to be on at all times, regardless of what is displayed. As a result, LCD screens tend to consume more power, particularly when displaying darker content, where power savings are not as significant as with OLED.

VI. Screen Lifespan and Burn-In Issues

OLED: A potential issue with OLED screens is "burn-in." If a static image is displayed for too long, it can cause the pixels in that area to degrade, leaving a permanent ghost image. Additionally, blue pixels in OLED screens degrade faster than others, potentially causing color distortion over time. However, modern OLED screens have optimized algorithms and pixel management technologies to reduce the likelihood of burn-in.

LCD: LCD screens do not suffer from burn-in, and their lifespan is relatively stable. Since liquid crystal pixels do not emit light, they do not experience the same aging effects as OLED. However, the backlight in LCD screens may fade over time.

VII. Price and Popularity

OLED: Due to its complex manufacturing process and higher material costs, OLED screens are generally more expensive than LCD screens. While the cost of OLED has decreased in recent years, it is still mainly used in high-end smartphones, flagship TVs, and emerging foldable devices.

LCD: LCD technology is mature and cheaper to produce, making it widely used in mid-range and budget devices like smartphones, tablets, laptops, and TVs. LCD still holds the majority of the global market share, especially in devices that prioritize cost-effectiveness.

VIII. Application Analysis

1. Smartphones:

· OLED Phones: High-end models such as Apple's iPhone Pro series and Samsung's Galaxy series use OLED screens. With exceptional color performance and contrast, they provide top-tier visual experiences. The slim design of OLED also contributes to the sleek aesthetics of these devices.

· LCD Phones: Some budget and entry-level smartphones, including older iPhone SE models and certain Android devices, still use LCD screens. While their display performance is somewhat inferior, their lower price remains a key selling point for many consumers.

2. Televisions:

· OLED TVs: Premium OLED TVs are known for their vibrant colors and high contrast, making them ideal for movie watching or applications requiring extreme display quality. OLED’s ultra-thin design also makes it highly desirable for modern TV aesthetics.

· LCD TVs: LCD TVs remain the mainstream choice, especially in the price-sensitive mid-range and entry-level markets. While their display quality doesn't match OLED's, they still offer a great viewing experience in daily use, with better brightness performance for well-lit environments.

IX. LCD vs. OLED Screen Comparison

Based on the screen characteristics mentioned above, the following table summarizes the comparison:

X. Eye Care Screen Selection Guide

Although OLED screens are generally more straining on the eyes and have a shorter lifespan compared to LCD screens, these are relatively minor differences that fall within an acceptable range. In terms of other performance aspects, OLED screens far surpass LCD screens and remain the dominant choice for flagship smartphones today.