What are the applications of borosilicate domes?
Shield: protects the internal optics or sensor.
Optical window: window element in an optical system.
Sensor protection: protects the sensor from environmental influences.
High temperature environment: high temperature imaging, high temperature sensors.

What are the advantages and disadvantages of borosilicate domes?
Advantages:
High heat resistance, good chemical stability, good mechanical properties, lower cost.

Disadvantages:
Lower UV transmittance, lower refractive index.

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