Performance requirements for glass tubes for LED lamps

The performance of the straight tube type LED lamp housing glass tube mainly includes the appearance effect, light transmittance, fogging degree, temperature and humidity resistance, moisture resistance, hardness, conductivity, expansion rate, bending degree, and the color parameters of the entire light.

Performance requirements for glass tubes for LED lamps

Key indicators are as follows:

①Appearance effect: Generally the color is milky white, the surface is smooth, no bubbles, no scratches, no spots, etc .;

②Transmittance: Test calculation method, using the same light source at the specified voltage and power respectively apply transparent glass tubes and milky white glass tubes of the same specifications, using an integrating sphere to its photoelectric color parameter test, milky white and transparent light effect. The ratio is the light transmittance. Generally, the light transmittance is required to be above 92%;

③Atomization degree: Put the matched light source (lamp beads) device in the glass tube, light the lamp at the rated voltage and power, and you can’t see the light-emitting point (lamp beads). Consistent performance, no obvious difference between light and dark;

④Temperature resistance: Put the glass tube in a high-temperature box of 150 ℃. After 200 hours, there is no color change, no burst, no deformation, etc .;

⑤Water resistance: Put the glass in a constant temperature water bath at 60 ℃. After 24 hours, there will be no color change, no cracks, no distortion, etc .;

⑥ Expansion coefficient fluctuation: The expansion coefficient fluctuation of the same batch of glass tubes shall be controlled within ± 1 × 10-7 / ℃;

⑦Conductivity: The inner and outer walls of the glass tube are required to be non-conductive;

⑧Light color effect: milk-white glass tube and transparent glass tube use the same light source to test light color parameters, and the spectrum, color temperature, and color rendering index must not be significantly different;

⑨Hardness: Take T8 glass as an example, the general pressure required to test the vertical pressure using a general glass pressure gauge is greater than 300N, which depends on the customers of each manufacturer

⑩ Bend: Take T8-1.2 meters long glass tube as an example, the bend is generally not required to exceed 3 °.

Among the above properties, most manufacturers pay more attention to the influence of light transmittance, fogging degree, temperature and humidity resistance, and light color.