Patent ID: 8714798

Claim:
An illumination module, comprising: a light bar having a first end and a second end opposite the first end, wherein a microstructure layer or a reflective layer is formed on the light bar, and a positioning pillar is formed on an outer side of the light bar; an LED assembly having at least one LED and being adjacent to the first end of the light bar, wherein the emitting light of the LED is diffused by the microstructure layer or reflected by the reflective layer to spread over the entire light bar; a positioning member connected with the second end of the light bar; a sleeve coupled between the light bar and the LED assembly to connect the light bar with the LED assembly; and a lamp receptacle coupled to the LED assembly; wherein the positioning member, the sleeve, the LED assembly or the lamp receptacle has at least one guide slot that engages with the positioning pillar of the light bar, the light bar has an inner side, the reflective layer is formed on the inner side or the outer side of the light bar, and the distribution of the reflective layer on the light bar satisfies the following condition: 1<tan θ=( R−H )/ W< 4.2, where angle θ is half a central angle of a cross-section of the light bar, with the central angle subtending an are that the reflective layer overlaps, R is a radius of the cross-section, W is half a chord subtending the central angle, and H is the apothem subtending the central angle and the chord.