automotive lighting - led road lighting

Automotive Lighting

Led Road Lighting

CANER GÖKSEL SONUZUN

Contents• What is Led?• How it Works?• Inside of an Led• Led Lighting• Advantages of Led Lighting• Disadvantages of Led Lighting• Automotive Led Lighting• Road Lighting

What is Led?• A light-emitting diode (LED) is a two-lead semiconductor light

source. It is a pn-junction diode, which emits light when activated.

How it Works?

• When a suitable voltage is applied to the leads, electrons are able to recombine with electron holes within the device, releasing energy in the form of photons. This effect is called electroluminescence, and the color of the light (corresponding to the energy of the photon) is determined by the energy band gap of the semiconductor.

Inside of an LED

Led Lighting

• With the development of high-efficiency and high-power LEDs, it has become possible to use LEDs in lighting and illumination. Replacement light bulbs have been made, as well as dedicated fixtures and LED lamps.

• An LED lamp is a light-emitting diode (LED) product that is assembled into a lamp (or light bulb) for use in lighting fixtures. LED lamps have a lifespan and electrical efficiency that is several times better than incandescent lamps, and significantly better than most fluorescent lamps, with some chips able to emit more than 100 lumens per watt

Advantages of Led Lighting• LED (Light Emitting Diodes) are the latest and most exciting

technological advancement in the lighting industry. LEDs are small, solid light bulbs which are extremely energy efficient and long lasting. LEDs operate differently than traditional incandescent light bulbs. This makes LEDs far more rugged and durable than traditional incandescent light bulbs. LED technology also offers many additional advantages over incandescent, neon and compact fluorescent lighting devices - such as exceptionally longer life span (60,000 hours), enormously lower energy usage (90% more efficient), reduced maintenance costs and higher safety. LEDs are currently being used for a wide variety of applications such as: residential lighting, aerospace, architectural lighting, automotive, aviation, broadcasting, electronic instrumentation, entertainment and gaming, industrial automation and controls, the military, traffic and safety & transportation.

Advantages of Led Lighting

Efficiency • LEDs are extremely energy efficient and consume up to 90%

less power than incandescent bulbs. Since LEDs use only a fraction of the energy of an incandescent light bulb there is a dramatic decrease in power costs. Also, money and energy is saved in maintenance and replacement costs due to the long LED lifespan.

• Because of the low power usage of LEDs, they are becoming extremely popular for light sources in remote areas that use solar panels.

• Although LEDs have a higher initial cost than incandescent and

compact fluorescent light bulbs, the cost is quickly recouped over time in lower electricity costs.


Longevity• LEDs have a lifespan of up to 60,000 hours compared to 1,500

hours for incandescent bulbs. An LED light will last over 7 years (constant use) before needing replacement. On average, LED bulbs last 10 times as long as compact fluorescent bulbs, and 133 times longer than typical incandescent bulbs. Long lifespan of LEDs will dramatically reduce maintenance costs and lower long-term operating costs compared to traditional incandescent and fluorescent tubes.

LED lifespan scenarios:• 50,000 hours powered 4 hours/day = 34 year lifespan• 50,000 hours powered 8 hours/day = 17 year lifespan• 50,000 hours powered 24 hours/day = 6 year lifespan


Durability • LEDs are solid state lighting devices that utilize semiconductor

material instead of a filament or neon gas. An LED light is a tiny chip encapsulated in an epoxy resin enclosure, which makes LEDs far sturdier than traditional incandescent light bulbs or fluorescent tubes. Since LEDs don't use fragile components such as glass and filaments, LEDs are able to withstand shock, vibration and extreme temperature.


Safety• Improved safety may be LED's most important benefit• LED lights generate virtually no heat therefore they are cool to

the touch and can be left on for hours without incident or consequence if touched. LED's produce 3.4 btu's/hour, compared to 85 for incandescent bulbs. In comparison, incandescent lighting expels 90% of the energy it consumes via heat, making the bulbs hot to the touch. LEDs reduce the potential for safety risks such as burns and fires.


Environment• LEDs are made from non toxic materials, unlike fluorescent lighting that uses

mercury that may pose a danger to the environment. LED’s are also recyclable and considered “green” or Earth-Friendly.

Color• LED lights are offered in a variety of base colors such as Red, Green, Blue

and Amber. Because traditional incandescent light bulbs use filters to produce colors, they are extremely inefficient. LEDS can be blended together to produce millions of color options.

Future• LEDs are poised to replace traditional incandescent light bulbs. LEDs are

rapidly becoming the preferred lighting solution of both professionals and residential users. LED technology is continually advancing - producing brighter LED bulbs. The U.S. Department of Energy hopes to reduce the electricity used for lighting by 50% by converting to LED based light sources.

Disadvantages of Led Lighting

• LEDs are currently more expensive, price per lumen, on an initial capital cost basis, than more conventional lighting technologies. However, when considering the total cost of ownership (including energy and maintenance costs), LEDs far surpass incandescent or halogen sources and begin to threaten compact fluorescent lamps.

Disadvantages of Led Lighting• The Chart Below compares different light sources based upon

the life of the bulb and the electrical cost at 10 cents per kWh (kilowatt hour). Note: fixture costs and installation costs are not included.

Disadvantages of Led Lighting• LED performance largely depends on correctly engineering the

fixture to manage the heat generated by the LED, which causes deterioration of the LED chip itself. Over-driving the LED or not engineering the product to manage heat in high ambient temperatures may result in overheating of the LED package, eventually leading to device failure. Adequate heat-sinking is required to maintain long life. The most common design of a heat sink is a metal device with many fins, which conducts the heat away from the LED.

• LEDs must be supplied with the correct voltage and current at a constant flow. This requires some electronics expertise to design the electronic drivers.

• LED’s can shift color due to age and temperature. Also two different white LED will have two different color characteristics, which affect how the light is perceived.

Automotive Led Lighting• Light emitting diodes (LED) are becoming more and more

significant in interior and exterior automotive lighting. The long service life, energy and space savings, shock and vibration resistance and new styling potential are the main advantages of using LEDs in automotive applications. Today, most central high mounted stop lamps use LEDs. In rear combination lamps the number of LEDs in amber and red is increasing rapidly. This year, a first rear combination lamp using LEDs for all functionalities including the back-up lamp function was realized. In addition, first signal functions in headlamps using white High Power LEDs were launched onto the market. The long service life characteristic makes LEDs especially predestined for the DRL function combined with the position/parking light.

Automotive Led Lighting - Headlamps

HeadlampsAutomotive headlamp applications using light-emitting diodes (LEDs) have been undergoing very active development since 2004.• In 2004 the Audi A8 W12 became the first production car to use

LED headlight technology, for the integrated daytime running lamps

• In 2006 the first series-production low beam, front position light and sidemarker function LED headlamps were factory-installed on the Lexus LS 600h / LS 600h L presented in 2007 for 2008 models. The high beam and turn signal functions use filament bulbs. The headlamp is supplied by Koito.


• In 2009 Hella headlamps on the 2009 Cadillac Escalade Platinum became the first US market all-LED headlamps.

• In 2010 the first all-LED headlamps with Adaptive highbeam and Intelligent Light System were introduced on the 2011 Mercedes-Benz CLS-Class: LED High Performance headlamps.

• In 2012 the first mechanically controlled LED glare free headlamps were introduced on BMW 7 Series Selective Beam (anti-dazzle High-Beam Assistant).


• In 2013 a (State of the art): First digitally controlled, full-LED glare-free adaptive highbeam. It was introduced by Audi on the facelifted Audi A8 in 2013, with 25 individual LED segments (Matrix LED). The system dims light that would shine directly onto oncoming and preceding vehicles, but continues to cast its full light on the zones between and beside them. This works because the LED high beams are split into numerous individual light-emitting diodes.high-beam LEDs in both headlights are arranged in a matrix and adapt fully electronically to the surroundings in milliseconds. They are activated and deactivated or dimmed individually by a control unit. In addition, the headlights also function as a cornering light. Using predictive route data supplied by the MMI navigation plus, the focus of the beam is shifted towards the bend even before the driver turns the steering wheel. In 2014: Mercedes-Benz introduced a similar technology on the facelifted CLS-Class in 2014, called MULTIBEAM LED, with 24 individual segments.


• Designs as of MY2010, such as those available as optional equipment on the 2010 Toyota Prius, give performance between halogen and HID headlamps, with system power consumption slightly lower than other headlamps, longer lifespans and more flexible design possibilities. As LED technology continues to evolve, the performance of LED headlamps is predicted to improve to approach, meet, and perhaps one day surpass that of HID headlamps


• The limiting factors with LED headlamps presently include high system expense, regulatory delays and uncertainty, and logistical issues created by LED operating characteristics. As a semiconductor, the performance of an LED is dependent on its temperature; a given diode will produce more light at a low temperature than at a high temperature. Thus, in order to maintain a constant light output, the temperature of an LED headlamp must be kept relatively stable. LEDs are commonly considered to be low-heat devices due to the public's familiarity with small, low-output LEDs used for electronic control panels and other applications requiring only small amounts of light; however, LEDs actually produce a significant amount of heat per unit of light output. Rather than being emitted together with the light as is the case with conventional light sources, an LED's heat is produced at the rear of the emitters. Unlike incandescent and HID bulbs, LEDs are damaged by high temperatures; prolonged operation above the maximum junction temperature will permanently degrade the LEDs and ultimately shorten the device's life. The need to keep LED junction temperatures low at high power levels requires thermal management measures such as heatsinks or cooling fans which are typically quite expensive.


• Additional facets of the thermal issues with LED headlamps reveal themselves in cold ambient temperatures. Not only can excessively low temperatures lead to the LED's light output increasing beyond the regulated maximum, but heat must in addition be effectively applied to thaw snow and ice from the front lenses, which are not heated by the comparatively small amount of infrared radiation emitted forward with the light from LEDs.

• LEDs are increasingly being adopted for signal functions such as parking lamps, brake lamps and turn signals as well as daytime running lamps, as in those applications they offer significant advantages over filament bulbs with fewer engineering challenges than headlamps pose.

Road Ligting

• Basic Principles of Streetlight Design • Design Considerations • Customer Requirements • Light Pollution• Basic Lighting Design

• Luminaire Selection

Basic Principles of Streetlight Design

• 1. Safety – pedestrian and driver safety. Creating a lighting level sufficient that drivers are aware of any pedestrians and or objects near the roadway.

• 2. Security – providing a setting that will deter some forms of criminal activity through the use and placement of lights.

• 3. Limit the amount of Light Trespass – avoiding the over lighting of areas such as in residential neighbourhoods where the backlight may shine on houses.

• 4. Environmental Responsibility • 5. To provide uniformity and consistency in lighting

designs throughout the province while meeting the industry standard.

Design Considerations• When starting a lighting design, attention to the surrounding

area and any special requirements must be taken into consideration, ie…schools, shopping districts, or airports.

• It is important to note that there are three different design methods that can be used for calculating the roadway lighting levels. Each method may produce different designs and provide different amounts of lighting levels through luminaire spacing and configurations. Each of these methods is acceptable and the preferred method SaskPower uses will be indicated later in this document. The three types are the Illuminance Method, Luminance Method and Small Target Visibility Method.

Customer Requirements• SaskPower’s standard practice is to design roadway lighting as

per TAC standards. There are situations where a customer may not wish to have streetlights designed to this standard, often due to the cost. If customer does not want to meet TAC requirements, they are required to sign a Streetlighting Waiver Form before SaskPower will install the streetlights. SaskPower will not install lighting facilities that do not meet the TAC requirements without this waiver as it would leave SaskPower open to liability.

Light Pollution

Light pollution is becoming an increasing concern and typically takes one of two forms: Light trespass or back lighting where there is an excessive amount of light towards a residence. Certain homeowners are particularly sensitive to light coming into their homes from streetlights and complain of sleep disruption, etc. While our typical luminaires do a reasonable job of controlling the light toward the residence, there have been complaints from homeowners regarding excessive light trespass. Mitigation may require selection of different luminaires, repositioning luminaires or the addition of light shields to block the light.

Light Pollution• Up-lighting where there is excessive light upwards from the

luminaire. This will impact visibility of the night sky and is a particular concern among astronomers. The International Dark-Sky Association (IDA) is an organization which promotes the use of luminaires with zero uplight (ie. Full Cut-off). They will assess luminaires and provide a Fixture Seal of Approval (FSA) for luminaires which meet their requirements for Uplighting. As of the writing of this document, the City of Saskatoon has required SaskPower install Full Cut-off lights

Basic Lighting Design • Roadway Terminology• Lighting Design Methodology • Pedestrian Conflict • Light Arrangement Styles • Pavement Classification • Area Classifications • Light Calculation Grid • Light Loss Factors

Roadway Terminology• Roadway – The portion of the road surface, including shoulders,

for vehicular use.• Traveled Way – The portion of the roadway provided for the

movement of vehicles, exclusive of shoulders, auxiliary lanes and bicycle lanes.

• Median – The portion of the roadway separating the traveled way for accommodation of stopped vehicles for emergency use, and for lateral support of the base and surface courses.

• Median – The portion of the roadway separating the traveled way for accommodation of stopped vehicles for emergency use, and for lateral support of the base and surface courses.

• Sidewalk – An exterior pathway with a prepared surface (concrete, bituminous, brick, stone, etc.) intended for pedestrian use.

Roadway Terminology

• Setback – The distance from the streetlight pole to the front of the curb.• Arm Length – The distance from the approximate location of the bulb to the

center of the vertical part of the light standard/pole. The typical arm length is 2.40m.

• House-side Lateral Distance – the distance from the imaginary vertical line directly below the luminaire and running back toward the adjacent curb. Also referred to as “Overhang”.

• Street-side Lateral Distance – the distance from the imaginary vertical line directly below the luminaire to the curb on the opposite side of the roadway.

• Mounting Height – the distance from the location of the bulb to the road surface directly below. The typical steel streetlight standard heights are: 25’, 30’, 35’, 40’, and 45’. There are also typical wood pole mounted streetlights.

Roadway Terminology

Lighting Design Methodology• There are three lighting design methodologies – Luminance, Illuminance

and Small Target Visibility (STV). Luminance measures the incident lighting on the roadway while illuminance is a measure of the reflected light.

• Small Target Visibility (STV) differs from Illuminance and luminance design in that values are given in terms of a weighted average visibility level. This is a relatively new design method adopted in 2000 by IESNA and has come under scrutiny within roadway lighting community. At this time STV should be used only as a method for assessing different lighting designs, and not as the primary method of calculation.

• The Luminance method shall be used for roadway and interchange, the Illuminance method shall be used for intersections and cul-de-sacs. Lighting designs for curved sections with greater than 600m radius should be evaluated as if it were a straight section, otherwise they should be evaluated as an intersection.

Pedestrian Conflict• The next step in developing a Roadway Lighting Design is to

identify the amount of pedestrian traffic in the area to establish the Average Illuminance, Average to Minimum Uniformity Ratio and Minimum Illuminance.

• According to IES RP-8-05, there are three types of classifications. • Low conflict area: residential • Medium conflict areas: schools, recreational centers • High conflict areas: restaurants, shopping, theatres

Pedestrian Conflict• Pedestrian Conflict is assumed to be the total number of people

on both sides of a street within a given section (200 meters). This number also includes those people crossing the street between the hours of 18:00 and 19:00.

LOW : 10 or fewer pedestrians

MEDIUM : 11 to 100 pedestrians

HIGH : over 100 pedestrians

Table - Classification of Pedestrian Conflict

Pedestrian Conflict

Light Arrangement Styles

There are several options available for the placement of lighting standards. Some of these are as follows:• One Sided Arrangement

Light Arrangement Styles• Two Sided Opposite Arrangement

• Two Sided Staggered Arrangement

Light Arrangement Styles• Double Davit Median Arrangement

Light Arrangement Styles• Double Davit Opposite Arrangement

Light Arrangement Styles• Double Davit Staggered Arrangement

Pavement Classification• The first step in developing the Roadway Lighting Design is to

determine the Pavement Classification. Pavement classification is a measure of how reflective the roadway surface is to establish the lighting levels required. The pavement classification will establish the Q0 Mean Luminance Coefficient.

• The four pavement classifications in TAC are R1, R2, R3, and R4. The R represents the reflective quality of the pavement. For SaskPower, a typical roadway would be represented by a R3 classification.

Pavement Classification

MODE OF

CLASS QO DESCRIPTION OF ROADWAY SURFACE REFLECTANCE

Portland cement concrete road surface. Asphalt road

R1 0.10 surface with a minimum of 15 percent of the

Mostly Diffuse

aggregate composed of artificial brightener *(e.g.

Synopal) aggregates (e.g. Labradorite, quartzite)

An asphalt road surface with an aggregate

R2 0.07 comprised of minimum 60% gravel (size greater Mixed (diffuse and

than 10mm). Asphalt road surface with 10-60% specular)

artificial brightener in aggregate mix.

An asphalt road surface (regular and carpet seal)

R3 0.07 with dark aggregates ( e.g. trap rock, blast furnace

Slightly Specular

slag); rough texture after some month of use

(typical highways).

R4 0.08 Asphalt road surface with very smooth texture Mostly Specular

C o p ie d fro m TAC 2-37 2006

Table - Pavement Classification

Area Classifications• In order to determine appropriate lighting levels, it is important to consider what

the land adjacent to the roadway is being used for, and in particular to identify the amount of pedestrian and vehicular traffic. There are three classifications:• Commercial. A business area of a municipality where ordinarily there are

many pedestrians during night hours. The definition applies to densely developed business areas outside, as well as within, the central part of municipality. The area contains land use which attracts a relatively heavy volume of night time traffic vehicular and or pedestrian traffic on a frequent basis.

• Intermediate. Those areas of a municipality often characterized by moderately heavy night time pedestrian activity such as in blocks having libraries, community recreation centers, large apartment buildings, industrial buildings or neighbourhood retail stores.

• Residential. A residential development, or a mixture residential and small commercial establishments, characterized by few pedestrians at night. This definition includes areas with single family homes, town houses, and or small apartment buildings.

Light Calculation Grid

• Setting up a grid in lighting design software should be as per IESNA RP-08-05. Using more or less points will alter the calculations and you may or may not achieve the proper lighting levels. As well any change of the grid spacing’s will also have an effect upon the calculations.

• The following criteria should be applied: • The grid should be based on the number of lanes for the majority of

the length of roadway. • In the event that the roadway width and number of lanes change,

then a revised grid should be used for the new length of roadway. • In the longitudinal direction, the distance between grid lines should

be one-tenth (1/10) of the spacing between luminaires, or 0.5m, whichever is smaller. The starting point for the gridlines should not be located directly under a pole, but should start instead at a point one-half (1/2) of the grid cell size from the luminaire pole.

Light Loss Factors• Light Loss Factors (LLF) are multiplier values to estimate the overall

performance at different times during the life of the lighting system. LLF values reflect the performance of the lamp and luminaire as well as the maintenance level of a lighting system. The LLF are:

• Lamp Lumen Depreciation (LLD)• Luminaire Dirt Depreciation (LDD)• Luminaire Ambient Temperature Factor (TF)• Ballast Factor (BF)• Equipment Factor (EF)

• The Light Loss Factor can be summed up as: LLF = LLD x LDD x TF x BF x EF

Light Loss Factors• LLD Lamp Lumen Depreciation

LLD is the reduction in the light output as the lamp ages. The rated Lumen are provided by the manufacturer based upon 100 hours of usage. The can be shown as ‘Lumen Depreciation curves”. The typical LLD factor for high pressure sodium vapour base on 5 year maintenance group re-lamping program is 0.78.• LDD Luminaire Dirt Depreciation LDD takes into account the luminaire output depreciation due to an accumulation of dirt on the luminaire and in the air. The designer should pick a ‘clean’ LDD value in most situations unless in an area of heavy manufacturing or areas prone to dust storm use moderate LLD value. The typical LDD value for a five year maintenance cycle adopted by SaskPower is 0.88.

Light Loss Factors• TF Luminaire Ambient Temperature Factor

TF accounts for variations in lumen output based on ambient temperature. HPSV luminaires are not affected significantly by ambient termperature, the TF adopted by SaskPower is 1.0.

• BF Ballast Factor BF is meant to cover reductions in light output due to the ballast. For HID sources it is assumed to be 1.0 unless otherwise noted by the manufacturer.

Light Loss Factors• EF Equipment Factor

EF is used to account for other reductions in light output due to the equipment used such as:

• manufacturing tolerances for both the luminaire and lamp • luminaire depreciating over time (reflective surface) • input voltage that varies from location to location SaskPower has

adopted an Equipment Factor of 0.95

Luminaire Selection • Lateral Light Distribution • Vertical Light Distribution • Cutoff Optics • Lighting Sources • SaskPower Luminaire Models

Lateral Light Distribution• Lateral Light Distribution is the lighting pattern the luminaire

puts out on the roadway. There are five types classified as Type I through V. The higher the Distribution Type number, the more light that will be spread across the roadway

• Type I - Usually used for median mounting.• Type I, Four Way – Mainly used for intersection lighting. This

light provides four beams of light from one light standard. An uncommon item and not very popular, would be placed in middle of intersection for proper lighting.

Lateral Light Distribution• Type II – Used to light the street front, not much light provided

on the back side of the luminaire.• Type II, Four Way – Mainly used for intersection lighting.

Provides four beams of light and is installed on a corner. This is an uncommon item and not very popular for lighting.

Lateral Light Distribution• Type III – Provides the majority of light to the roadside of the

luminaire while the backside does not project as much light.

• Type IV - Provides the majority of light to the roadside of the luminaire while the backside does not project as much light. The Type IV puts light out further from the curb than a Type III.

Lateral Light Distribution• Type V – Ideal to be installed in the center of the intersection

and puts out a light pattern that is evenly dispersed around its axis.

• Type V Quadrate – has a square form of light pattern around its axis.

Vertical Light Distribution• Vertical light distribution is divided into three categories, Short,

Medium and Long as illustrated in Figure 5-10. Classification is on the basis of the distance from the luminaire to where the beam of maximum candlepower strikes the roadway surface. The classifications are:

• Short Distribution – The maximum candlepower beam strikes the roadway surface between 1.0 and 2.25 times mounting heights distance from the luminaire. See Figure 5-11.

• Medium Distribution – The maximum candlepower beam strikes the roadway surface between 2.25 and 3.75 times mounting height distance from the luminaire.

• Long Distribution – The maximum candlepower beam strikes the roadway surface between 3.75 and 6.0 times mounting height from the luminaire.

Vertical Light Distribution• On the basis of the vertical light distribution, theoretical

maximum candlepower beams from adjacent luminaires are joined on the roadway surface. With this assumption, the maximum spacing of luminaires are:

• Short Distribution – 4.5 X mounting heights• Medium Distribution – 7.5 X mounting heights• Long Distribution – 12.0 X mounting heights• From a practical standpoint, the medium distribution is

predominantly used in practice, and the spacing of luminaires normally does not exceed five to six times mounting heights. Short distribution is not used extensively for economic reasons, because extremely short spacing is required. At the other extreme, the long distribution is not used to any great extent because the high beam angle of maximum candlepower often produces glare.

Vertical Light Distribution

Half Maximum Candlepower Projection

Cutoff Optics• The amount of glare generated by a luminaire is strongly

influenced by the intensity (candle-power) emitted at angles close to the horizontal. The cutoff classification is based on the intensity of rays emitted at 80-degrees and 90-degrees vertical angle. As the intensity of either of these angles will vary in different vertical planes for typical roadway luminaires, the maximum intensity considering all planes is used

• Non-Cutoff• no intensity limits apply. • are designed to allow for light to be emitted in all directions.

These are the least efficient of the four types to light a roadway due to the amount of light pollution and glare they produce. Post-top lights without shrouds or shielding are often Non-Cutoff.

Cutoff Optics• Semi-Cutoff• are designed so that the intensity at 80 degrees vertical angle must

not exceed 20% of the rated lamp lumens, and the intensity at 90 degrees must not exceed 5 % of the rated lamp lumens.

• are designed to allow the majority of light to be emitted below 90 degrees, with up to 5% allowed to be emitted above 90 degrees. The most common type of light that fits this description is the Cobrahead.

Cutoff Optics• Cutoff• has more controlled emitted light than semi-cutoff. Less than

2.5% of the emitted light is allowed to escape the fixture above 90 degrees. The light spread is greater than a full cutoff, and the spacing is not as far apart as a semi-cutoff.

• are designed so that the intensity at 80 degrees vertical angle must not exceed 10% of the rated lamp lumens, and the intensity at 90 degrees must not exceed 2.5% of the rated lamp lumens.

Cutoff Optics• Full Cutoff• are designed so that light will only hit the ground below with no

light escaping above 90 degrees. The light is in a tight pattern on the ground which requires the use of more lights than if one were using any of the other three types of lamps.

• are designed so that the intensity at 80 degrees vertical angle must not exceed 10% of the rated lamp lumens, and no light can be emitted at 90 degrees or above. Full cutoff normally requires that the luminaire have a flat bottom opening.

• Full Cutoff luminaires may have an International Dark Sky Fixture Seal of Approval (see section 5.2 Light Pollution).

Cutoff Optics Luminaire Cutoff

Classification

Cutoff Optics• Reduction of Glare with Full Cutoff Luminaire

Cutoff Optics• Reduction in Light Trespass From Full Cutoff

Thank you for your attention…

• Presented by

Caner Göksel Sonuzun.

automotive lighting - led road lighting

Engineering