What is optically transparent silicone?
Optically transparent silicone is a type of organic silicone material with high transparency and wide application in the optical field. It has unique properties and diverse uses:
1. Chemical composition and structure
Basic ingredients: Based on polysiloxane as the base polymer, the main chain of the molecule is composed of alternating silicon atoms and oxygen atoms (-Si-O-Si-), and the side chains are usually organic groups such as methyl and phenyl. This special structure gives silicone both the stability of inorganic silicon oxygen bonds and the flexibility of organic groups.
Crosslinking system: Through crosslinking agents (such as hydrogen-containing silicone oil, etc.) and catalysts (such as platinum catalysts), linear polysiloxane molecules undergo crosslinking reactions to form a three-dimensional network structure, which improves the physical properties of silicone, such as strength, hardness and heat resistance.
2. Characteristics
High transparency: In the visible light band (380-780nm), the transmittance of optically transparent silicone can reach more than 90%, which is close to optical glass, and can meet application scenarios with high requirements for light transmittance.
Good optical stability: Its optical performance is stable under long-term light and temperature change environment, and it is not easy to yellow or age, ensuring that the transmittance and other optical properties remain basically unchanged during long-term use.
Excellent thermal stability: It can maintain stable performance in a wide temperature range (-50℃ to 200℃ or even higher), does not decompose or produce bubbles at high temperature, and does not become brittle at low temperature. It is suitable for working scenes with high temperature environment or large temperature changes.
Electrical insulation: It has good electrical insulation performance, low dielectric constant and dielectric loss, and can provide electrical insulation protection in electronic optical devices to prevent leakage, short circuit and other problems.
Flexibility and buffering: After curing, it forms a soft elastomer, which can effectively buffer external stress, reduce damage to optical components due to vibration and impact, and improve device reliability and service life.
Chemical corrosion resistance: It has good tolerance to water, most organic solvents, acids, alkalis and other chemicals, and can protect optical components from corrosion in a variety of chemical environments.
3. Application fields
Optical display:
LED packaging: used for LED chip packaging to protect the chip from the external environment, while improving the light output efficiency and making the light more uniform and soft.
LCD/OLED bonding: as a bonding material between the display screen and the touch panel, it improves the overall light transmittance and display effect of the screen and enhances the impact resistance of the screen.
Optoelectronic devices:
Fiber optic connection and coupling: used for the connection between optical fiber and optoelectronic devices, plays a role in fixing, sealing and optical conduction, and ensures efficient transmission of optical signals.
Optical sensor protection: encapsulate optical sensors to provide physical protection and environmental isolation for sensors while ensuring normal light incidence and emission.
Optical lens:
Lens bonding: used for bonding and fixing between lens components to ensure accurate lens position without affecting optical performance.
Lens protective coating: coated on the surface of the lens to enhance the lens's wear resistance, scratch resistance and anti-pollution ability while maintaining high light transmittance.