PCB Tech - Talk about FPC fingerprint module board technology

FPC fingerprint module

The fingerprint module is the core component of the fingerprint lock, which is installed on devices such as fingerprint access control or hard disks, mobile phones, etc., to complete fingerprint collection and fingerprint identification. The fingerprint module is mainly composed of a fingerprint acquisition module, a fingerprint identification module and an extended function module (such as a lock drive module), and the FPC fingerprint module is an important component.

FPC fingerprint module can be divided into:

1. Optical fingerprint module, which recognizes fingerprints by the principle of light refraction and reflection;

2. Capacitive fingerprint module, which collects fingerprints by changing the value of capacitance;

3. Radio frequency fingerprint module (scratch fingerprint module), which uses trace radio frequency signals to detect lines.

Principle of FPC fingerprint module:

1. Optical fingerprint module, using the principle of light refraction and reflection, the light is emitted from the bottom to the prism, and then emitted through the prism. The emitted light will be refracted on the uneven lines of the fingerprint on the surface of the finger and the reflected light will be bright or dark. Different. The CMOS or CCD optical device will collect the image information of different brightness and darkness to complete the fingerprint collection.

2. The semiconductor fingerprint module, whether it is capacitive or inductive, has similar principles. On a "flat" integrated with thousands of semiconductor devices, a finger is attached to it to form the other side of the capacitor (inductance).,

Due to the unevenness of the finger plane, the actual distance between the convex point and the concave point contacting the plate is different, and the formed capacitance/inductance value is also different. The device will collect the different values according to this principle. The fingerprint collection is completed.

3. The radio frequency fingerprint module uses the bio-radio frequency fingerprint identification technology to emit a small amount of radio frequency signal through the sensor itself, which penetrates the epidermis of the finger to control and measure the lines of the inner layer to obtain the best fingerprint image. The anti-counterfeit fingerprint ability is strong, and the principle of radio frequency identification only reacts to the human dermal skin, which fundamentally eliminates the problem of artificial fingerprints.

The use of FPC fingerprint module:

1. Verify fingerprint

2. Register to add fingerprints

3. Conditional delete fingerprint

4. Forcibly delete fingerprints

Technical parameters of FPC fingerprint module:

PCB size (mm) 58*58; acquisition head resolution 500DPI; fingerprint capacity 50 (expandable to 200); dynamic current <140mA; standby current <18?A; working voltage 5-7.5V.

Live fingerprint module (capacitive fingerprint module):

Full-width fingerprint sensor (area sensor); the surface of the sensor is coated with a special protective paint to be strong and scratch-resistant, the finger placement method adopts an ergonomic design, and the FPC flexible cable connection seat is adopted.

1. Complete functions: independently complete fingerprint collection, fingerprint registration, fingerprint comparison and fingerprint search functions;

2. Good anti-counterfeiting: reflective induction detection technology, live fingerprint detection function, with the ability to distinguish fingerprints and fake fingerprints;

3. Strong adaptability: The algorithm has excellent performance and has excellent adaptability to all kinds of fingerprints, such as dry fingers, wet fingers, and light-textured fingers, which have a high recognition rate and good correction and fault tolerance performance;

4. Strong antistatic ability: strong antistatic ability, especially suitable for areas where the environment is dry and prone to static electricity;

5. Application development is simple: development can be based on the provided control instructions, self-development of fingerprint application products, without the need to have professional fingerprint recognition knowledge;

6. Small size: The sensor is small in thickness and small in size, and can be flexibly embedded in various products with limited volume;

7. Strong ease of use: large fingerprint collection area, light touch fingerprint collection process, easy to use;

8. Data encryption: encrypted storage and secure encrypted transmission, and the algorithm complies with relevant security standards.

Optical fingerprint module

The full name is optical total reflection fingerprint sensor.

FPC product features: The fingerprint collection head all-in-one machine sends and receives instructions through UART; realizes fingerprint data registration and comparison under minimum storage conditions: the fingerprint template is 498 bytes (the function is especially suitable for storing fingerprints in contact IC cards or non-contact Type IC card to verify whether the card holder is himself).

Scratch fingerprint module

Features:

1. It can flexibly adapt to the finger conditions at the time, whether it is dry fingers, wet fingers, light-textured fingerprints, elderly fingers, etc., have a high recognition rate;

2. It can automatically end image collection, and the image quality is getting better and better;

3. Strong anti-counterfeit fingerprint ability. The identification principle of fingerprint sensor only reacts to human dermal skin, which fundamentally eliminates the problem of artificial fingerprints;

4. Strong antistatic ability: it is very suitable for dry areas where static electricity is easy to generate;

5. Wide temperature zone: suitable for particularly cold or extremely hot areas;

6. Ultra-thin volume: can be embedded in various terminal products;