How to choose the writing desk lamp

time2011-10-25

  Writing lamp light source has three general categories: incandescent, halogen and fluorescent lamps.
  To be able to most of the light projected onto the desktop, writing desk lamp light source position is usually installed horizontally or downward.
  Writing desk lamp in a normal working position, the optical performance requirements of the main three points:
  (1) shading: one case in a normal sitting position, eyes to the horizontal direction, should not see the inside of shade and light;
  (2) Desktop illumination requirements: lamp illumination of work area should be ≥ 250lx, the illumination should be ≥ 120lx;
  (3) illumination uniformity requirements: should ensure that the work area illumination lamps, illumination is relatively uniform, not a particularly bright or dark spot.
  Writing lamp purchase, in addition to checking the optical properties, we must also check the other properties, the method is as follows:
  1、a pull, two tone, three pan, four touch. "Pull" refers to the power cord plug from the socket, pull the power cord hard to light cavity, to see the power cord connections are secure. Power cord can not be detached from the lamp chamber. "Transfer" refers to regulate a variety of lamp working position. Adjustment can not be audible, adjusted work location should be easy and reliable locking. "Shake" refers to the lamp adjusted to the most adverse working position, then gently shake the lamp placed on a plane to see whether the lamp is easy to tip over, stable lamp is bad, it is easy to tip over. "Touch" refers to the lamp lit for some time (2 hours), hand-to-use shade and other heating components are easily accessible hot, to prevent accidental burns when used in future.
  2、such as bulk purchase of lamps, it is best to light the lamp and switches and other electrical components removed, burned with a lighter plastic holder or switch for 10 seconds, then remove the fire source, the plastic can in 30 seconds from put out the fire performance is generally satisfactory. Such as the purchase of electronic ballast fluorescent lamp, the lamp can be broken into a lamp, and then after a few minutes to see power electronic ballasts for damage. There are exceptions to protect the electronic ballast circuit is not damaged.