The difference between white light LED and other light sources

With the rapid development of white light LED technology, many practical and impractical solutions have been proposed. Here we analyze the lighting applications and prospects of LED by comparing some basic characteristics.
First, we need to clarify two concepts:

power

Luminous flux: The light energy passing through a certain area per unit time is called the radiant energy flux passing through this area. The unit is lumen.

When we evaluate a light source, we generally need to look at its several characteristics: power, luminous efficiency, light characteristics, and price.
Power is the commonly used input power of the light source. For example, a 100W incandescent lamp means that its input power is 100W. Each light source can cover a large power range. Here we only compare the commonly used power range.
Luminous efficiency is the ability of the light source to convert electrical energy or other inputs into light energy. We use luminous flux as the evaluation standard for light energy. The unit of this efficiency is (lumens/watt), which indicates the ability of the light source to convert each watt of energy into lumens.
Light characteristics refer to the color, luminous area, and light divergence angle of the light source. Light characteristics often determine the application range of a light source. For example, lasers have good directionality and can be used for distance measurement, while fluorescent lamps have good divergence and are suitable for indoor lighting.
Prices vary greatly due to different powers. We approximately take the price required for every 1000 lumens to make a rough comparison. At the same time, the difference in power consumption caused by different luminous efficiency will be briefly analyzed later in the article.

Here is a simple diagram to illustrate:

The common light sources in the table have their clear uses, and white light LED is a product that is still developing. Its application range needs to be further developed in addition to the current flashlights, headlights, portable devices and other occasions.
It can be clearly seen from this table that in addition to the slight advantages of LED in light characteristics and other characteristics, it is completely at a disadvantage in terms of power and price.
Especially the price, which is the most fatal factor limiting the current application range of LED. The power limitation makes LED unable to be used for large-scale lighting, such as airports, construction sites, and even indoor lighting. LED cannot be compared with fluorescent lamps.
In practical applications, when the power of lighting equipment is large, the power consumption is also a cost that cannot be ignored. However, in front of fluorescent lamps and HIDs with higher light efficiency, LEDs cannot take any advantage.
Before there is a major breakthrough in power and price, the promotion of LED lighting can be said to be difficult. Although many cities have invested in the construction of some public LED lighting equipment, in the current situation, this behavior is nothing more than a waste of taxpayers' money.
In addition, the advantages of colored LEDs for decoration are relatively more obvious, because when ordinary light sources are turned into colored light sources, their luminous efficiency will generally decrease, and LEDs have almost absolute advantages in the field of colored light efficiency. Unfortunately, as a traditional decorative lamp, neon lights have reached a very high cost-effective level, and it is not easy for LEDs to replace them.
The only strength of LEDs at present is the lighting of small-volume, low-voltage devices, such as mobile phones and DC and other household digital products. These products are expensive in themselves, so the relatively expensive defect of LEDs becomes less obvious.
Based on the above analysis, despite the rapid development, white light LEDs still face considerable obstacles in entering the lighting field. Before these obstacles are effectively removed, we still need to be cautious about the promotion of white light LED lighting.