Optical fingerprint sensor VS semiconductor fingerprint sensor, which fingerprint smart lock is better?

Dec 31, 2019

We will find when selecting: There are basically two types of fingerprint locks on the market, one is optical fingerprint recognition, and the other is semiconductor fingerprint recognition. In addition, semiconductors are generally more expensive than optics. But because we are not very familiar with the differences and their respective advantages, we will inevitably feel difficult when choosing. Next, I will take a closer look at optical fingerprint recognition and semiconductor fingerprint recognition for you.


● Optical fingerprint sensor

Fingerprinting with optical technology is the oldest and most widely used technology. Put your finger on the optical lens, the finger is projected on the CCD (Charge Coupled Device) with a prism under the illumination of the built-in light source. Furthermore, the digitized lines with a certain width and direction in the fingerprint image are black, and the depressions between the fingerprint lines are white. Forms fingerprint images that can be processed by fingerprint device algorithms.

● Semiconductor fingerprint sensor

Whether it is capacitive or inductive, the principle is similar. Fingers rest on a panel of thousands of semiconductor devices. Due to the unevenness of the plane of the finger, the actual distance between the bump and the point of contact with the flat plate is different, and the capacitance (inductance) value is different. The device summarizes the different values collected according to this principle and completes fingerprint collection.


Optical fingerprint recognition Advantage 
1: strong adaptability and easy to cleanThe optical fingerprint recognition module has strong environmental adaptability. The optical fingerprint head acquisition window is generally made of tempered glass, which can enhance the compression and abrasion resistance, acid resistance, and stain corrosion to a certain extent. The optical fingerprint recognition module adaptability to the working environment is good, and the surface is easy to clean. It can be used in special environments with high humidity, high temperature and dust.


2. Longer life

The optical fingerprint recognition module has good stability. Optical fingerprint recognition technology has been tested and continuously improved by the market ethics. In addition, the optical fingerprint head has better adaptability to the market environment. Longer life in theory.

3.Low cost

The optical fingerprint recognition module has low manufacturing cost. The development of optical fingerprint heads is relatively early, and there is already a mature industry scale, which can be mass-produced modularly. The raw materials used for optical fingerprint heads are relatively cheap, so the cost of optical fingerprint heads is generally cheaper than semiconductor fingerprint heads.


1. Insufficient accuracy

There are certain inherent defects in the recognition accuracy of optical fingerprint heads. Optical fingerprint head is a different imaging of fingerprint ridge and valley to light reflection. For users with shallow fingerprints, too dry fingerprints, or peeling skin, they will be prone to misidentification.


2. Large power consumption

Optical fingerprint recognition consumes relatively large power. Optical fingerprint heads need to emit strong light, so it requires more power than semiconductor fingerprint heads. Generally, the optical fingerprint lock needs to be replaced once more than six months. The semiconductor fingerprint lock can be used for about one year.

Semiconductor fingerprint recognition


1: living body recognition

The semiconductor fingerprint recognition module only recognizes a living fingerprint, and has high security. In other words, the semiconductor fingerprint head can penetrate the surface layer of the skin. So the silicone analog fingerprints that are rumored on the Internet are basically useless here. The advantage of identifying a living fingerprint lock is that the fingerprint cannot basically be copied.


2.Very high sensitivity and recognition accuracy

Semiconductor fingerprint recognition consists of tens of thousands of capacitors in a capacitor array. Collecting fingerprint ridges and valleys to the touch panel to form fingerprint data. Compared with optical scanning accuracy is better. It can collect more accurate fingerprint details, and the collection speed is faster.

3.High module recognition rate

The optical fingerprint head will be affected by the wet, dry, and shade of the fingerprint during normal use, resulting in recognition errors and unrecognizable fingerprints. Semiconductors can minimize these problems.

4. Other characteristics

In addition, semiconductors have characteristics such as low power consumption and small size. It is very helpful for reducing the power consumption of smart locks and reducing the size of locks.


1.High cost

The capacitive plate of the semiconductor fingerprint identification module is obviously more expensive than the tempered glass of the optical fingerprint module. Of course, the cost of other components is also relatively higher than the optical fingerprint module, so the cost is higher. But with the development of the industry, the price difference between the two has gradually become smaller.

2. Not easy to maintain

The semiconductor fingerprint recognition module is not easy to maintain. The collection window of the semiconductor fingerprint head is affected by stains, sweat, and static electricity, and it is easy to be scratched. Therefore, pay attention to protection and conservation when using it. Otherwise, the service life is difficult to guarantee.


In the current industry, in addition to the dominant optical and semiconductor fingerprint locks, there are some companies and research teams developing ultrasonic unlocking, face recognition unlocking, voice unlocking, face + voiceprint unlocking, etc., as well as gestures, body language , Voice, iris technology. These are all interactive tools for smart locks. There are also opportunities in the future intelligent era. Realize the technological revolution of smart door locks.