Abstract— For the sake of pursuit ofbrighter light beam, the phenomena that consumers themselves replace thehalogen light source in the headlamp of their car with HID light source havebeen prevalent in China for a long time. Usingthe same socket as headlamp with halogen light source, modified headlamp withHID light source can easily generate more than two times the light volume onthe road as the standard halogen light sources meanwhile has cheaper price.However, such headlamps pose big problems to the testing originations becausethat none of the relevant national standards (such as GB4599-2007, GB21259-2007,etc.) can be used as the suitable one in the testing process. Furthermore, thereis almost no research focusing on the photometric performance of HID modifiedheadlamp so far, since it is not an easy thing to evaluate the photometric performanceof a headlamp. As a result, there is still some ambiguity whetherthe HID modified headlamps have security problems during nighttime drive or howthe photometric performance of such headlamps is.

In 2010,CIE TC4-45 “Lighting and Signaling for Transport” issued a technical reporttitled “Vehicle Headlighting Systems Photometric Performance-Method ofAssessment” (CIE 188 Technical Report). This report specified the methods toassess the photometric performance of vehicle headlighting systems and thusenable the performance of different headlighting systems to be compared. Sincethe methods in this technical report did not take the light source of aheadlamp into account, it can be also used to evaluate the photometricperformance of HID modified headlamps.

In thispaper, we compare the photometric performance of three kinds of headlamps:headlamp with halogen light source, headlamp with HID light source and HIDmodified headlamp. The headlamps, which are not modified, belong to the car ofsame type but with different configuration, while the modified one is assembledby using the socket of the headlamp with halogen light source and the lightsource of headlamp with HID light source. Using the method described in the CIE188 Technical Report, these three kinds of headlamps were evaluated by thecriteria of range, width and glare. Then a total score was calculated from thesingle criteria for every headlamp. Thus the comparison was madefeasible. The results of the comparison were an application of the methodsdescribed in the CIE 188 Technical Report. It is hoped that the results couldbe a reference advice for development the relevant regulations about modifiedheadlamps in China.

Keywords-modified headlamp; photometric performance; CIE 188 Technical Report ; assessment