Sub-circular lights, square lights, rectangles, surface light tubes, lateral tubes, surface mounted microtubes, etc. The circular lamp is divided into φ2mm, φ4.4mm, φ5mm, φ8mm, φ10mm and φ20mm according to diameter. In general, φ3mm LEDs are referred to as T-1; φ5mm is referred to as T-1 (3/4); and φ4.4mm is referred to as T-1 (1/4).
The angular distribution of circular luminous intensity can be estimated from the half-value angle. There are three types of luminous intensity distributions:
(1) High directionality. It is generally pointed epoxy package, or with a metal reflective cavity package, and no scattering agent. Half-value angle of 5 ° ~ 20 ° or less, with a high degree of directivity, can be used as a local lighting source, or combined with the optical detector to form an automatic detection system.
(2) Standard type. Usually used as indicator light, its half-value angle is 20 ° ~ 45 °.
(3) Scattering type. This is an indicator with a larger viewing angle, with a half-value angle of 45° to 90° or more and a large amount of scattering agent.
