Application Note

Light Emitting Diode

Thermal Design
Considerations for
Nichia NVSW719AC LEDs

Table of contents
1. Overview ............................................................2
2. NVSW719AC LEDs ..........................................2
3. Thermal Design Considerations.................3
4. How to Measure/Calculate theTemperatures ................................................6
5. Thermal Evaluation ...................................... 10
6. Examples of Modules with Different
Heat Dissipations ...................................... 13
7. Summary ......................................................... 15

The Nichia part number NVSW719AC within this document is merely Nichia’spart number for the Nichia product and is not related nor bear resemblance
to any other company’s product that might bear a trademark.

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Application Note
1. Overview

Figure 1. Appearance of the
NVSW719AC LED

2. NVSW719AC LEDs
2.1 Outline Dimensions and Input Power
Figure 2 provides the outline dimensions of the NVSW719AC LEDs. Figure 3 shows acomparison of the input power for Nichia LEDs with the same package area. The amount ofheat generated from the LED increases in proportion to the increase of the input power.
Therefore, the thermal design is very important for the NVSW719AC LEDs to minimize theincrease in the LED temperature.
光学的中心位置
Location of the optical center

2719 Series
519 Series

3.5

Light Emitting Diode

When an LED is exposed to high temperatures for a long period oftime, the components and/or materials used in the LED will
deteriorate, leading to degradation of the performance, reliability,
and lifetime of the LED. Therefore, proper thermal design isimportant to achieve the performance that is specified in theapplicable specification of the LED.
Since the Nichia NVSW719AC LEDs require a large input power, thethermal design may be challenging. However, if the increase of the
LED temperature can be minimized by appropriate heat dissipation,
it is possible to design more compact luminaires with a higher
luminance than conventional LEDs. This application note provides
the thermal evaluation method for the NVSW719AC LEDs.

319 Series
219 Series
Cathode Mark

2

0.4
0.88

3.5

Figure 2. Outline Dimensions of the(Unit: mm)

0

5

10

(W)

Figure 3. Comparison of the Input Power 1

NVSW719AC LED

2.2 Structure and Thermal Paths of the NVSW719AC LEDs
Figure 4 shows a reference image of the structure and thermal paths of the NVSW719AC
LED. The main heat sources are the LED chip and the phosphors. The heat generated fromthe LED chip and the phosphors mainly dissipates to the PCB and heatsink through thesubstrate and the electrodes of the LED. Since the NVSW719AC LEDs are designed to have ahigh luminance, the light density of the small emitting surface is high. This may cause the1

The ranges between the rated power consumption and the maximum rated power consumption are compared. The series numbers
shown in this figure are Nichia LED series used for comparison with the NVSW719AC LEDs (i.e. 719 Series).

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Application Noteamount of heat generated in the phosphor layer of the LED to increase, resulting a higher
temperature of the emitting surface than that of the LED chip. In the NVSW719AC LEDs,
temperature control is important not only for the LED chip (junction temperature) but also
for the emitting surface.
Emitting Surface (Phosphor Layer)
Reflecting Material

Phosphor (Heat Source)

Substrate

LED Chip (Heat Source)Electrode

Light Emitting Diode

Figure 4. Reference Image of the Structure and Thermal Paths

3. Thermal Design Considerations
3.1 Thermal Resistance Model and Descriptions of the Terms
Figure 5 shows a thermal resistance model for the NVSW719AC LED. Table 1 shows the terms
and descriptions that are used herein.
TT
LED
SolderPCBHeatsink

RθTJ
TJ(RθTS)
RθJS

TS

RθSA
TA

Figure 5. Thermal Resistance Model for the NVSW719AC LED

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Application Note
Table 1. Terms and Descriptions Related to Thermal Design

Light Emitting Diode

Term

SymbolLED Surface
TemperatureTT

LED Junction
Temperature

TJ

Solder Joint
Temperature

TS

Ambient
Temperature

TA

Thermal Resistancefrom the LED
Emitting Surface tothe LED Chip

RθTJ

Thermal Resistancefrom the LED Chipto the Solder Joint

RθJS

Thermal Resistancefrom the LED
Emitting Surface to
the Solder Joint
Thermal Resistancefrom the PCB to the
Ambient Air via the
Thermal Interface
Materials

Description and Main Precautions
Temperature of the LED emitting surface. If the LED surface temperature ishigh, a decrease in the luminous flux, color shift, and degradation of thereliability may occur due to deterioration of the resin-based components
used in the LED.
Nichia recommends that the LED surface temperature does not exceed
180˚C when using the LED.
Temperature of the LED chip. The thermal design must not exceed theabsolute maximum junction temperature. The absolute maximum junction
temperature of the NVSW719AC LEDs is 150˚C.
Note that the lifetime of the LED is determined by the derating
characteristic of the LED junction temperature. Customers can contact a
local Nichia sales representative for details.
Temperature of the solder joint at the LED cathode electrode side. The
solder joint temperature at the cathode electrode side is measured byusing a thermocouple to conduct a thermal evaluation.
When the LEDs are used under hightemperatures, there are concerns such as
solder deterioration and solder cracks; Nichia
recommends operating the LED at the lowest
solder joint temperature possible.
The “Solder Temperature (Cathode Side) vs.
Allowable Forward Current” is shown in the
figure to the right (see the “DERATINGCHRACTERISTICS” section of the specification
for the NVSW719AC LEDs for the details).
Ensure that the LED is operated at a solder
joint temperature of 100°C or less.
Ambient temperature of the LED. If the heat dissipation of the chosen
application (e.g. sealed fixtures) is not good around the LED module dueto the design of the chosen application, note that the TA and the TJ will behigher.
Thermal resistance from the LED emitting surface to the LED chip.
The thermal resistance value varies depending on the color rank and thecolor rendering index rank as it is mainly related to the properties of thephosphors.
Thermal resistance from the LED chip to the solder joint. Using this thermal
resistance value, the LED junction temperature can be calculated based on
the temperature of the solder joint and the input power.

RθTS

Thermal resistance from the LED emitting surface to the solder joint. Using
this thermal resistance value, the LED surface temperature can becalculated based on the temperature of the solder joint.

RθSA

Thermal resistance from the solder joint to the ambient air via the thermalinterface materials. It is the combined resistance of the thermal interface
materials including the PCB, thermal grease, and the heatsink.

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Application Note
3.2 Soldering Pad PatternFigures 6 and 7 show the electrode configuration of the NVSW719AC LED and arecommended soldering pad pattern for NVSW719AC LEDs. The die heatsink electrode has
the largest effect on the heat dissipation. The die heatsink electrode is electrically insulated
inside the LED, and this allows the cathode electrode and the die heatsink electrode shownin Figure 8 to be connected with the copper layer of the PCB. Having such a larger copper
layer pattern immediately under the die heatsink electrode enables the generated heat tospread to the PCB efficiently.

Light Emitting Diode

0.4

0.5

1.3

3.3

0.45

1.2

0.5

2.4
3.2

3.2
1.3

➞ Thermal Path
LED’s Outlines and the Electrodes■ Copper Layer■ Solder Resist

Cathode Electrode

Cathodeダイヒートシンク
Die Heat Sink

0.5

Anode

(Unit: mm)

Figure 6. Electrodes on the
LED Back Surface

Die Heatsink Terminal

4.1(Unit: mm)

Figure 7. Recommended
Soldering Pad PatternFigure 8. Example of Soldering
Pad Pattern

3.3 Components Used with the LEDs
When components (e.g. secondary optical lens, cover, etc.) are used with the LED, ensurethat heat and light emitted from the LED emitting surface do not affect these components(see Figure 9). Table 2 shows typical heat resistance temperatures for the materials of the
optical components used with the LEDs for reference.
Note that if foreign materials (e.g. flux, dust, particles, etc.) have adhered to the LED emitting
surface and/or the components used with the LEDs, the foreign materials may be heated by
the intense light emitted from the LED, causing burns and/or the occurrence of smoke (seeFigure 10).
Table 2. Typical Heat Resistance Temperatures of Materials (For Reference) 2
Material
Acrylic
Polycarbonate
Glass
Silicone

2

Typical Heat Resistance
Temperature
70 to 90˚C
120 to 130˚C>200˚C>200˚C

These are typical temperatures and vary depending on the types of materials and their specifications.

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Application NoteMaterial: Acrylic

Figure 9. Example of Deformation of aSecondary Optical Lens due to Heat

Figure 10. Examples of Burnt LED Emitting
Surface and Secondary Optical Lens
due to Flux AttachedLight Emitting Diode

4. How to Measure/Calculate the Temperatures
For proper thermal evaluation of the NVSW719AC LED, the temperature of the solder joint(TS), the junction temperature (TJ), and the LED surface temperature (TT) will need to beobtained. This section explains how each of the temperatures is measured or calculated.
4.1 How to Measure the Solder Joint Temperature (TS)As shown in Figure 11, attach a thermocouple to the solder joint area (the cathode side) tomeasure the solder joint temperature (TS). Ensure that a thermocouple with a small and thin
tip is used to avoid affecting the thermal dissipation. Also, ensure that the LED emitting
surface is free from contamination (e.g. flux, adhesive) before attaching the thermocouple tothe solder joint area.

Figure 11. Example of How a Thermocouple is Attached with an Adhesive

4.2 How to Calculate the LED Junction Temperature (TJ)
There are the following two methods for calculating the LED junction temperature. Thesemethods are briefly explained below.
- Calculating the LED junction temperature (TJ) in accordance with JESD51 standard- Calculating the LED junction temperature (TJ) based on the solder joint temperature (TS)and the input power

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Application Note
4.2.1 How to Calculate the LED Junction Temperature (TJ) in accordance with JESD51
Standard
Nichia obtains the LED junction temperature (TJ) in accordance with the method detailed in
the JESD51 standard. Nichia usually obtains the LED junction temperature (TJ) by measuring
the forward voltage (ΔVF) that has a correlation with the TJ; however, for the NVSW719AC
LEDs, the peak wavelength (λP) of the LED chip that has better linearity than the forward
voltage (ΔVF) is used to obtain the TJ. The calculation method is shown below.

Constant Temperature
Chamber（TA1, TA2, TA3, ・・・）

Measurement
Current (IFP)

Intensity (-)

・・・

Detector

TA1
TA2
TA3

λP
↓

λP (nm)First, the LED is operated with the pulse current (IFP), which is the same as the operating
current (IF) and can minimize the heat generation, while the temperature of the LED is
maintained at a certain temperature within a constant temperature chamber. Then, theemission spectrum (the peak wavelength of the LED chip [λP]) is measured (see Figure 12).
This procedure is repeated at different temperatures for the constant temperature chamber.
Since no LED self-heating affecting the measurement occurs, the LED junction temperature
becomes the same temperature as that of the constant temperature chamber. Using thesevalues, the relationship between the junction temperature and the peak wavelength isobtained as shown in Figure 13.

・・・

Spectroscope

TJ (℃)

Wavelength (nm)Figure 13. Relationship Between the Junction
Temperature and the Peak Wavelength

Figure 12. Measurement Circuit

4.2.1.2 Peak Wavelength Measurement and Obtaining the Junction Temperature

Ambient Temperature（TA）
Detector

OperatingCurrent (IF)λP (nm)To measure the peak wavelength, the LED is operated with the operating current (IF) until the
LED thermally saturates (see Figure 14). Using the relationship between the junction
temperature (TJ) and the peak wavelength shown in Figure 13, the TJ can be obtained basedon the measured peak wavelength (see Figure 15).

Intensity (-)

Light Emitting Diode4.2.1.1 Obtaining the Relationship between the Junction Temperature and the Peak
Wavelength✕

Spectroscope✕
λP

Figure 14. LED Chip’s Peak Wavelength
Measurement

Wavelength (nm)

TJ (℃)

Figure 15. How to Obtain the LED Junction
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Application Note
For the NVSW719AC LEDs, the junction temperature and thermal resistance are obtainedusing the above procedures.3 This measurement requires dedicated equipment and is notsuitable for luminaries or modules. Nichia recommends the following calculation method
based on the solder joint temperature (TS) and the input power.
4.2.2 Calculating the Junction Temperature (TJ) based on the Solder Joint Temperature (TS)and the Input Power (W)The junction temperature can be calculated by using the solder joint temperature measured
with a thermocouple, the thermal resistance (RθJS), and the input power (the forward voltage[VF] × the operating current [IF]).
For the equation and the thermal resistance required for the calculation, refer to Equation 1
and Table 3 below, or the applicable specification. Nichia recommends using the maximum
thermal resistance to have a margin for the design.

Light Emitting Diode

Equation 1: TJ = TS + RθJS × W
TJ = LED Junction Temperature (˚C)
TS = Solder Joint Temperature (˚C)
RθJS = Thermal Resistance from the LED Chip to the Solder Joint (˚C/W)
W = Input Power (W)Table 3. Thermal Resistance (RθJS) of the NVSW719AC LED4

Thermal Resistance (RθJS)

3
4

Unit

Typ.

Max.

˚C/W

2.5

3.5

The calculation method used by Nichia may be changed without notice for improvements of the measurement accuracy.
The maximum value is for reference purposes only (PCB used: the aluminum thickness = 1.5mm, the copper layer thickness = 35μm).

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Application Note
4.3 How to Measure the LED Surface Temperature (TT)Light Emitting Diode

When measuring the LED surface temperature (TT), use a non-contact type thermal imaging
camera. If a contact type measurement device such as a thermocouple is used, the sensor
and/or the adhesive used for attaching the thermocouple are exposed to light and theirtemperatures become high, which may result in inaccurate measurement values.
When measuring the LED surface temperature (TT), ensure that the temperature of the centerarea of the emitting surface is measured as shown in Figure 16. Note that when the resolutionof the thermal imaging camera is low, the temperature is averaged, which may also result ininaccurate measurement; use a thermal imaging camera with a resolution suitable for thesize of the chosen application.
If the LED is covered with an optical lens and/or cover, it is impossible to measure the LED
surface temperature (TT) using infrared thermography. In this case, it is necessary to calculate
the approximate LED surface temperature (TT) based on the solder joint temperature (TS)measured by a thermocouple. For the relationship between the solder joint temperature (TS)and the LED surface temperature (TT), refer to the evaluation results in Sections 5 and 6.

Emissivity used for Measurement: 0.95

Figure 16. Measurement Location for the LED Surface Temperature

Figure 17. Example of Measurement Using a Thermal Imaging Camera

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Application Note
5. Thermal Evaluation
Nichia measured the solder joint temperature (TS) and the LED surface temperature (TT).
5.1 Evaluation Conditions
5.1.1 Evaluated LEDs
In white LEDs, the lower the color temperature and/or the higher the color rendering index,
the higher the phosphor concentration, causing the amount of heat generated from thephosphors to increase accordingly. In this evaluation, the LEDs with the following ranks wereused as representative samples that have a large or small amount of heat.

Light Emitting Diode

Sample 1: NVSW719AC LEDs with color rank of sm27 (equivalent to color temperature
2700K), and color rendering index (CRI) of R9050 (equivalent to Ra≥90)
Sample 2: NVSW719AC LEDs with color rank of sm40 (equivalent to color temperature
4000K), and color rendering index (CRI) of R9050 (equivalent to Ra≥90)
Sample 3: NVSW719AC LEDs with color rank of sm50 (equivalent to color temperature
5000K), and color rendering index (CRI) of R9050 (equivalent to Ra≥90)
Sample 4: NVSW719AC LEDs with color rank of Cr70 (equivalent to color temperature
7000K), and color rendering index (CRI) of Rnn (Ra is not specified.)
5.1.2 PCB and Heatsink Used
The PCB and heatsink used for this evaluation are as follows:
PCB:
Material:
Insulating Layer:- Thermal Conductivity5:- Thickness:
Copper Layer Thickness:
Soldering Pad Pattern:

Aluminum (Thickness: 1mm)
2.7W/m・K
120μm
35μm
See Nichia’s recommended pattern on Figures 7 and 8.

Heatsink:
Dimensions (For Reference):
50mm×38mm×25mm
6Thermal Resistance (For Reference) :5.77˚C/W

Figure 18. PCB and Heatsink Used for the Evaluation
5
6

The thermal conductivity is the value stated in the PCB manufacture’s data sheet.
The thermal resistance is the value obtained from a simulation.

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Application Note
5.1.3 Operating Current
Level 1:
Level 2:
Level 3:

IF = 500mA
IF = 1050mA (Sorting Current)
IF = 1500mA (Absolute Maximum Rating Current)

5.2 Evaluation Method
Nichia operated the evaluation LEDs at the ambient temperature (TA) of 25˚C in a windlessenvironment and then measured the solder joint temperature (TS) and the LED surface
temperature (TT) after the saturation temperature had been reached.
A thermocouple was used for the TS measurement, and a thermal imaging camera was used
for TT measurement.
In addition, the LED junction temperature was calculated based on the measured TS and thethermal resistance (RθJS) of 3.5˚C/W.

The measurement results of the solder joint temperatures (TS) and the LED surface
temperatures (TT) are shown in Figures 19 to 22 as well as the LED junction temperatures (TJ)
calculated based on the TS.
200

150
TS
TJ
TT

100
50

Temperature (ºC)

Temperature (ºC)

200

150
TS
TJ
TT

100
50
0

0
0

500

1000

1500

0

2000

500

1000

1500

2000

Forward Current (mA)

Forward Current (mA)

Figure 19. Measurement Results of the

Figure 20. Measurement Results of theLEDs with Rank of sm27/R9050

LEDs with Rank of sm40/R9050

200

200

150
TS
TJ
TT

100
50

0
0

500

1000

1500

2000

Forward Current (mA)

Figure 21. Measurement Results of theLEDs with Rank of sm50/R9050

Temperature (ºC)

Temperature (ºC)

Light Emitting Diode

5.3 Evaluation Results

150
TS
TJ
TT

100
50
0
0

500

1000

1500

2000

Forward Current (mA)

Figure 22. Measurement Results of theLEDs with Rank of Cr70/Rnn

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Application Note
The LED surface temperatures (TT) are higher than the LED junction temperatures at theoperating currents as shown in Figures 19 to 22. Care should be taken because the lower thecolor temperature is, the higher the LED surface temperature (TT) will be.
When designing a luminaire, the LED surface temperature (TT) must be measured as well as
the LED junction temperature (TJ) and ensure that the TJ and TT do not exceed the absolute
maximum junction temperature or Nichia’s recommended maximum LED surface
temperature.

Figures 23 to 26 show the thermal resistances (RθTS) from the LED emitting surface of the LED
to the solder joint that were obtained based on Figures 19 to 22. When conducting a thermal
evaluation, the approximate LED surface temperature (TT) can be calculated from the solder
joint temperature (TS) by using these thermal resistances. For the calculation, see Equation 2
below. The thermal resistance used in the calculation should be obtained from the graphdata whose combination of the LED rank and forward current are equivalent to those actuallyused in the chosen application.
10.0

Thermal Resistance (RθTS)(ºC/W)

Thermal Resistance (RθTS)(ºC/W)

10.0
9.0
8.0
7.0
6.0
5.0
4.0
0

500

1000

1500

9.0
8.0
7.0
6.0
5.0
4.0
0

2000

500

1000

1500

2000

Forward Current (mA)

Forward Current (mA)

Figure 23. Measurement Results of the

Figure 24. Measurement Results of theLEDs with Rank of sm27/R9050

LEDs with Rank of sm40/R9050

10.0

Thermal Resistance (RθTS)(ºC/W)

10.0

Thermal Resistance (RθTS)(ºC/W)

Light Emitting Diode5.4 How to Calculate the LED Surface Temperature (TT)

9.0
8.0

7.0
6.0

5.0
4.0
0

500

1000

1500

2000

Forward Current (mA)

Figure 25. Measurement Results of theLEDs with Rank of sm50/R9050

9.0

8.0
7.0

6.0
5.0

4.0
0

500

1000

1500

2000

Forward Current (mA)

Figure 26. Measurement Results of theLEDs with Rank of Cr70/Rnn

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Application Note
Equation 2: TT = TS + RθTS × W
TJ = LED Surface Temperature (˚C)
TS = Solder Joint Temperature (˚C)
RθTS = Thermal Resistance from the LED Surface to the Solder Joint (˚C/W)
W = Input Power (W)

6. Examples of Modules with Different Heat Dissipations
Nichia evaluated three modules with different heat dissipations. When considering thethermal design for the chosen application, use the following data for reference purposes.
6.1 Structures/Dimensions of the Modules Used for the Evaluations

Light Emitting Diode

Table 4 shows the structures and dimensions of the modules used for the evaluations.
Table4. Structures/Dimensions of the Modules Used for the Evaluations

Module 1

Module 2

Module 3

NVSW719AC
sm27/R9050
Φ20mm
Aluminum(Thickness: 1.0mm)

Same as Module 1
Same as Module 1
Φ40mm

Same as Module 1
Same as Module 1
Φ60mm

Same as Module 1

Same as Module 1

2.7 W/m∙K

Same as Module 1

Same as Module 1

Φ23.5mm×14mm

Φ40mm×27mm

66mm×75mm×40mm

19 ˚C/W

10 ˚C/W

1.9 ˚C/W

Appearance

LED UsedPart No.
Color Rank
Size
Material

PCB

Heatsink

ThermalConductivity of
the Insulating
Material7
Size
ThermalResistance7

6.2 Evaluation Method
Nichia operated the evaluation LEDs at the ambient temperature (TA) of 25˚C in a windlessenvironment and then measured the solder joint temperature (TS) and the LED surface
temperature (TT) after the saturation temperature had been reached.
A thermocouple was used for the TS measurement, and a thermal imaging camera was used
for TT measurement.
In addition, the LED junction temperature (TJ) was calculated based on the measured TS andthe thermal resistance (RθJS) of 3.5˚C/W.

7

The thermal conductivity is the value stated in the PCB manufacture’s data sheet.

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Application Note
6.3 Evaluation Results

250

250

200

200

150

TS
TJ
TT

100
50

150

TS
TJ
TT

100

50
0

0
0

500

1000

1500

0

2000

500

1000

1500

2000

Forward Current (mA)

Forward Current (mA)

Figure 27. Measurement Results of Module 1

Figure 28. Measurement Results of Module 2(Φ20mm)(Φ40mm)250
Temperature (ºC)

Light Emitting Diode

Temperature (ºC)

Temperature (ºC)

The evaluation results are shown in Figures 27, 28, and 29.

200

150

TS
TJ
TT

100
50

Nichia’s Recommended Maximum
LED Junction Temperature (TJ) (150˚C)
Nichia’s Recommended Maximum
LED Surface Temperature (TT) (180˚C)

0
0

500

1000

1500

2000

Forward Current (mA)

Figure 29. Measurement Results of Module 3(Φ60mm)In the case of Module 1 with a low heat dissipation due to the small-sized heatsink, the LED
junction temperature (TJ) reaches to the absolute maximum junction temperature at
IF=800mA; thus, applying a forward current exceeding IF=800mA must be avoided. In thecase of Module 2, the LED surface temperature (TT) exceeds Nichia’s recommended
maximum LED surface temperature of 180˚C at IF=1200mA; thus, applying a forward current
exceeding IF=1200mA is not recommended. To achieve higher output power for the
NVSW719AC LEDs, the heat dissipation must be equivalent to Module 3, where the TJ and TT
did not exceed the absolute maximum junction temperature or Nichia’s recommended
maximum LED surface temperature, or it must have higher heat dissipation than Module 3.
The evaluation results shown in this application note were obtained at an ambient
temperature of TA=25˚C. When designing a luminaire, it is necessary to consider the ambient
temperature rise resulting from the LED being hermetically sealed with an optical cover
and/or housing.

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Application Note
7. Summary

Light Emitting Diode

To maximize the high luminance and the high output power of the NVSW719AC LEDs,
efficient thermal dissipation is essential. Customers are required to perform sufficient
thermal evaluations of the chosen application prior to use by using this application note asa reference and to ensure that the chosen application has an enough margin.
The evaluation results and the thermal resistances (RθJS) detailed in this application note wereobtained under Nichia’s evaluation conditions and environments. These results andmeasurement values may vary depending on the conditions and environments in which thechosen application is actually used; these results and values should be used for reference
purposes only.

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Application Note

Light Emitting Diode

Disclaimer
This application note is a controlled document of Nichia Corporation (Nichia) published toprovide technical information/data for reference purposes only. By using this applicationnote, the user agrees to the following: This application note has been prepared solely for reference on the subject matters
incorporated within it and Nichia makes no guarantee that customers will see the same
results for their chosen application.
 The information/data contained herein are only typical examples of performances and/or
applications for the product. Nichia does not provide any guarantees or grant any licenseunder or immunity from any intellectual property rights or other rights held by Nichia or
third parties.
 Nichia makes no representation or warranty, express or implied, as to the accuracy,completeness or usefulness of any information contained herein. In addition, Nichia shallnot be liable for any damages or losses arising out of exploiting, using, or downloadingor otherwise this document, or any other acts associated with this document.
 The content of this application note may be changed without any prior or subsequent
notice.
 Copyrights and all other rights regarding the content of this document are reserved by
Nichia or the right holders who have permitted Nichia to use the content. Without priorwritten consent of Nichia, republication, reproduction, and/or redistribution of thecontent of this document in any form or by any means, whether in whole or in part,
including modifications or derivative works hereof, is strictly prohibited.

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TOKUSHIMA 774-8601, JAPAN
Phone: +81-884-22-2311 Fax: +81-884-21-0148

NICHIA CORPORATION
http://www.nichia.co.jp

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