• 한국자동차공학회논문집
• /
• 제10권4호
• /
• pp.158-165
• /
• 2002

This Paper deals with the headlamp lens surface temperature distribution of p/c headlamp using the three categories of H4 halogen bulbs. Glass is gradually replaced by P/C for the lens material off vehicle headlamp due to the weight reduction and stream lined body of a vehicle. With this trend, the newly established standards for a headlamp with a P/C lens in Europe requires that the heat generated by a bulb should not distort the lens surface. Also the requirements fur the bulb of a headlamp are being enforced in U.S.A & Europe. However, such requirements are not established yet in Korea. By using three kinds (60/55w, 100/90w, 130/90w) of H4 halogen bulbs in this experiment, the surface temperature distribution and Max. temperature on the lens were measured. The results of this study implies the necessity of requirement fur the bulb off headlamp.

• 조명전기설비학회논문지
• /
• 제25권4호
• /
• pp.1-6
• /
• 2011

The elder population with 65 years old or more in Korea has been entered into an aging society as 9.1[%] in 2005 to 14.3[%] in 2018. The elder population in 2026 will be expected to 20.8[%] with the rapid aging society. In this study, there has been conducted a study on development of headlamp for elder friendly vehicle in order to ffrom two different groups, one group for elder with over 65 ages, the other group for compared ages(20 ages, 30~50 ages). Glare test and forward visibility test were performed on wet and dry road conditions. As the result of these tests, it showed to prefer headlamp installed partially yellow coated bulb, which gives warm feeling on dry road condition. Forward visibility of headlamp which developed to fit on wet road condition is similar to existing HID headlamp. Glare was evaluated less than halogen and HID headlamp. However, it need to more improve glare and forward visibility performance of headlamp for old drivers.

• 전기학회논문지
• /
• 제59권5호
• /
• pp.890-896
• /
• 2010

Increasing styling features for automotive headlamps speed up the focus of understanding condensation at inner surfaces. Water vapor condensation on the inside surface of the headlamp lens is an essential factor that affects secure front view and headlamp life. One of the headlamps of automobile which is one of the most popular in Korea was chosen for the present analysis. In the basis of the experimental data of automobile given by a manufacturer, boundary conditions were defined and free convection of the air inside the headlamp and radiation from the bulb to the other surfaces are considered. As a result, temperature distribution of the inside surface of the headlamp lens are approximately the same as the experimental result.

• 전기전자학회논문지
• /
• 제27권4호
• /
• pp.368-378
• /
• 2023

LED 매트릭스를 사용하는 차량용 헤드램프에서 LED의 디지털 제어는 I2C, SPI 등의 저가격 저속 직렬 버스를 사용하여 왔으나 헤드램프의 해상도가 증가하면서 LED 제어를 위해 전송해야 하는 데이터의 양이 너무 많아 제어 버스의 전송 능력을 초과하게 된다. 본 논문에서는 새로운 차량용 LED 매트릭스 헤드램프 제어 프로토콜인 HLCP(Headlamp LED Control Protocol)을 제안한다. 제안하는 프로토콜은 많은 LED를 하나의 명령어로 제어하는 명령어를 사용하여 I2C 버스를 거의 그대로 사용하면서도 훨씬 많은 LED를 제어할 수 있다. 제안하는 프로토콜을 수행하는 컨트롤러를 Verilog HDL로 구현 및 검증하였으며 시뮬레이션 결과 LED 매트릭스 헤드램프를 I2C나 SPI보다 효율적으로 제어할 수 있음을 확인하였다.

• Journal of Mechanical Science and Technology
• /
• 제16권11호
• /
• pp.1404-1411
• /
• 2002

A newly developed high intensity discharge (HID) automotive headlamp results in a high luminous gradient at the cutoff line, and proves the superior concept in safer and more com-fortable nighttime driving. This new headlamp technology Provides drivers expanded night vision by a significantly improved light pattern. However, the HID headlamp may dazzle other traffics during traversing a rough road or encountering an unexpected bump. To resolve this problem, an automatic headlamp leveling device is necessary. A preview control is presented for the design of the leveling system. The proposed control algorithm is capable of attenuating a dynamic glare which is one of the major detractors to a driving in dark roads. Computer simulations using ADAMS are carried out to confirm the effectiveness on the control system.

• 한국자동차공학회논문집
• /
• 제22권7호
• /
• pp.23-30
• /
• 2014

"Cut off line" in automotive passing beam has very important safety function because it serves for headlamp aiming. Headlights that are aimed incorrectly will not only perform poorly but also offend oncoming traffic. In addition, an objective definition of cut off line in low beam is necessary, since a requirement for correct aiming of the beams is specified within all the existing regulations. Accordingly, headlight regulations are requirements that automobiles must satisfy in order to be sold in a particular country. In this study, a more advanced recognition method for the cut off lines of the various headlamps commonly used in Europe, North America, and domestic is suggested and a headlamp testing system is developed to adjust the beam to the country-specific regulation. This system uses image processing technology to detect the cut off lines in the beam patterns of halogen headlamps, high-intensity discharge headlamps, and light-emitting diode headlamps as well.

• 한국전기전자재료학회논문지
• /
• 제28권8호
• /
• pp.544-549
• /
• 2015

Since LEDs (light emitting diodes) have many advantages as a light source in vehicle headlamp, such as good reliability, energy and space saving, and flexible headlamp design. On the other hand, the dependence of its performance and life on temperature have great influence on its practical use. In this study, design and fabrication of heat sink for vehicle LED headlamp were performed using thermally-conductive plastics. This study focused on the effective heat sink structure with limited space in the vehicle LED headlamp. We designed two different prototype of heat sink by thermal simulation using SolidWorks program, which had excellent temperature characteristics. The two different prototype of heat sink were fabricated by injection molding with thermally-conductive plastics. The results showed that LED $T_j$ (junction temperature) of sample B (model 1) and sample C (model 1, 2) was below then $165^{\circ}C$ when applying the thermally-conductive plastics in heat sink of vehicle LED headlamp.

• Current Optics and Photonics
• /
• 제1권4호
• /
• pp.351-357
• /
• 2017

This paper proposes a LED bicycle headlamp with a wide viewing angle to help bicyclists see the front effectively and because of its high visibility to reduce the risks of accidents around intersections or blind spots. The wide viewing angle was determined to be $28^{\circ}$ because it can illuminate a 5 m wide area 10 m away. Therefore, the road conditions of the intersection can be observed with the bicycle handlebar tilted slightly to the left or right. The headlamp has a compact reflector with a width of 30 mm, height of 27 mm, and length of 17 mm. Owing to its size, a change in the position of a light source leads to severe changes in light distribution. Therefore, the tolerance of the source position was analyzed by a simulation. The tolerance was ${\pm}0.5mm$ at the X, Y and Z axes within a less centered aiming range of ${\pm}1^{\circ}$. Finally, the prototype of the bicycle headlamp was made and the light distribution was measured by an automotive headlamp light measurement system. The experimental results indicate that the headlamp illuminates a 5 m wide area with an edge light of 3.2 lx as well as meeting the K-mark regulation.

• 대한인간공학회지
• /
• 제29권4호
• /
• pp.575-584
• /
• 2010

The aim of study is to suggest the design procedure of automobile headlamp by considering driver's experience in regard of the visibility and glare during nighttime driving. The characteristics of driver were investigated in terms of the drivers' cognitive ability and reaction time, headlamp specification and visibility, light source and glare. And, the degree of visual discomfort was categorized and recognized as a tool to represent the subjective user experience. The UX point of view was stated when the existing results were seemingly lacking of it. The visual comfort and safety of elderly drivers were also discussed by reviewing the studies of ageing regarding the visibility and driving responses. Finally, this study suggested how to reduce the negative effect of nighttime driving due to the height of headlamp, angle of lighting, color spectrum, discomfort glare, source of light by using the UX perspective and methodology.

• 조명전기설비학회논문지
• /
• 제29권10호
• /
• pp.65-72
• /
• 2015

Recently, LED light has been increasingly adopted for vehicles in both domestic and foreign automotive markets, while a variety of LED lights have been developed to be used particularly for headlamps. In this paper, we propose an H-type resonant snubber circuit topology for high efficiency of vehicle LDM (LED Driver Module) and realized LDM functions for vehicle headlamp by designing high-efficiency convertors. In addition, this study reduced the financial burden by configuring the system to control the whole with micom except for the use of individual dedicated chips to drive LED for high and low beam. In order to verify the validity of the proposed H-type resonant snubber capable of soft switching, simulations were performed using PSIM. As a result, the validity was experimentally verified by creating a prototype. Moreover, in order to actually attach the headlamp, the performance of the proposed convertor was confirmed by designing LDM to the limited size. Communications between the headlamp and higher controller were realized using LIN(Local Interconnect Network).