| 摘要 |
<p>PURPOSE:To provide the line head which has high light emission intensity and is reducible in power consumption by specifying the relation between the refractive index of a damp proofing agent and the refractive index of a cover member. CONSTITUTION:The line head 17 has a cover member 29 which consists of covers 25, 26, and 27 and a spacer 28 and covers an end surface light emission type EL element 2, and the damp proofing agent 30 is charged in the internal space of this cover member 29. Further, the line head 17 has an injection opening 32 for the damp proofing agent 30 in one end of the upper cover 25 of the cover member 29 and also has an air discharge opening 33 in the other end, and those air discharge opening 33 and injection opening 32 are sealed by adhering a sealing plate 34. This line head 17 satisfies relations ns>nb and ns>ng, where nb is the refractive index of the cover member 29 and ng is the refractive index of a transparent substrate 8. Therefore, the scattering of the projection light of the end surface light emission type EL element 2 can be reduced.</p> |
