Tektronix LumaColor II J18 Instruction Manual
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Tektronix LumaColor II J18 Instruction Manual

Tektronix LumaColor II J18 Instruction Manual

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J18
LumaColor II Photometer
Instruction Manual
070-9021-03
This document applies to firmware version 2.00
and above.
Warning
The servicing instructions are for use by qualified
personnel only. To avoid personal injury, do not
perform any servicing unless you are qualified to
do so. Refer to the Safety Summary prior to
performing service.

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  • Page 1 LumaColor II Photometer Instruction Manual 070-9021-03 This document applies to firmware version 2.00 and above. Warning The servicing instructions are for use by qualified personnel only. To avoid personal injury, do not perform any servicing unless you are qualified to do so.
  • Page 2 Copyright Tektronix, Inc. All rights reserved. Tektronix products are covered by U.S. and foreign patents, issued and pending. Information in this publication supercedes that in all previously published material. Specifications and price change privileges reserved. Printed in the U.S.A. Tektronix, Inc., P.O. Box 1000, Wilsonville, OR 97070–1000...
  • Page 3 EC Declaration of Conformity Tektronix Holland N.V. Marktweg 73A 8444 AB Heerenveen The Netherlands declare under sole responsibility that the J18 LumaColor Photometer meets the intent of Directive 89/336/EEC for Electromagnetic Compatibility. Compliance was demonstrated to the following specifications as listed in the official Journal of the European Communities: EN 50081–1 Emissions:...
  • Page 5 Tektronix, with shipping charges prepaid. Tektronix shall pay for the return of the product to Customer if the shipment is to a location within the country in which the Tektronix service center is located. Customer shall be responsible for paying all shipping charges, duties, taxes, and any other charges for products returned to any other locations.

  • Page 7: Table Of Contents

    Table of Contents General Safety Summary ......Service Safety Summary ......viii Preface .
  • Page 8 Table of Contents Reference RS-232D Operation ....... . . 3–1 RS-232 Pin Connections .
  • Page 9 Table of Contents List of Figures Figure 1–1: Low Battery Warning Icon ....1–3 Figure 1–2: Replacing the Battery ..... . . 1–4 Figure 1–3: Location of J18 Power Adapter Connector .
  • Page 10 Table of Contents List of Tables Table 2–1: Factory Preset 6500 K White Values ... 2–9 Table 3–1: RS-232D Parameters ..... . . 3–1 Table 3–2: Measurement Units .

  • Page 11: General Safety Summary

    General Safety Summary Review the following safety precautions to avoid injury and prevent damage to this product or any products connected to it. Only qualified personnel should perform service procedures. Injury Precautions Do Not Operate in Wet/Damp Conditions To avoid electric shock, do not operate this product in wet or damp conditions.
  • Page 12 General Safety Summary Do Not Immerse in Liquids Clean the probe using only a damp cloth. Refer to cleaning instructions. Safety Terms and Symbols Terms in This Manual These terms may appear in this manual: WARNING. Warning statements identify conditions or practices that could result in injury or loss of life.
  • Page 13 General Safety Summary Symbols on the Product The following symbols may appear on the product: Double DANGER Protective Ground ATTENTION Insulated High Voltage (Earth) Terminal Refer to Manual J18 Photometer Instruction Manual...

  • Page 14: Service Safety Summary

    Service Safety Summary Only qualified personnel should perform service procedures. Read this Service Safety Summary and the General Safety Summary before performing any service procedures. Do Not Service Alone Do not perform internal service or adjustments of this product unless another person capable of rendering first aid and resuscitation is present.

  • Page 15: Preface

    Preface This manual contains information to support user operation and service of the J18 LumaColor II Photometer. The manual is divided into User and Service sections that are separated by a yellow page. User Information The user information details the control and operation of the photometer.
  • Page 16 Preface J18 Photometer Instruction Manual...

  • Page 17: Getting Started

    Getting Started...

  • Page 19: Product Description

    Product Description The J18 is a digital photometer, radiometer, and colorimeter. The interchangeable J1800 series sensor-heads provide the ability to make a variety of light measurements. J18 LumaColor II Photometer Features The J18 provides the following features: Real-time color measurements Auto zero Readings in either English or metric units RS-232D interface for remote control...

  • Page 20: Unpacking The J18 Lumacolor Ii Photometer

    3. Cushion the instrument on all sides with packing material. Seal the carton with shipping tape or with an industrial stapler. 4. If you are shipping the product to a Tektronix Service Center, be sure to label the carton with the name of your company, a person to contact at your company, and a description of the problem.

  • Page 21: Power Options

    Power Options The J18 may be powered by either of two sources: A non-rechargeable nine-volt alkaline battery An external AC power adapter, available as an optional accessory. (See the Replaceable Parts section for information about available accessories.) NOTE. When switching between power sources, cycle the photometer power off and then on again to enable the photometer to auto-zero using the new power source.

  • Page 22: Battery Installation

    Power Options Battery Installation CAUTION. Follow the manufacturers’ guidelines for the handling and disposal of batteries. To replace the alkaline battery (refer to Figure 1–2): 1. Turn off the J18. 2. Open the battery compartment located on the back cover of the J18.

  • Page 23: Using The Optional Ac Power Adapter

    Power Options Using the Optional AC Power Adapter The J18 may be powered with the optional external AC power adapter. The power adapter will override the internal battery if one is installed. To ensure accurate measurements, cycle the photometer power off and then on again to permit the photometer to autozero using the new power source.
  • Page 24 Power Options J18 Photometer Instruction Manual 1–6...

  • Page 25: Functional Check

    Functional Check The J18 performs a self-test when first turned on. The self-test is successfully completed under the following conditions: A “fresh” battery must be installed, or the AC adapter must be attached. A recognized sensor head must be attached. (The J18 will not recognize the J1820 sensor head.) 1.

  • Page 26: Figure 1-5: Typical Display Test

    Functional Check 3. After the auto-zero is complete, all of the display characters are shown as a display test. See Figure 1–5. – – Figure 1–5: Typical Display Test 4. After the display test is complete, the display shows the firmware version that is installed.

  • Page 27: Figure 1-7: Typical Zero Display

    Functional Check 5. After the firmware version is displayed, the photometer initially displays zeros until the sensor cover is removed. See Figure 1–7. Figure 1–7: Typical Zero Display 6. Remove the cover from the sensor head and aim the sensor to take a measurement.

  • Page 28: Figure 1-9: Typical Single Channel Display

    Functional Check If the attached sensor head is a single channel sensor, the photometer displays only one value for the measurement. See Figure 1–9. Figure 1–9: Typical Single Channel Display 7. If a sensor head is not attached, or the sensor head is not recognized, the J18 flashes the error message shown in Figure 1–10.

  • Page 29: Operating Basics

    Operating Basics...

  • Page 31: Functional Overview

    Functional Overview This section provides a overview of the controls, indicators, and operation of the photometer. J18 Front Panel Connect a J1800 Series sensor head here. The POWER switch turns the J18 on or All readings appear off. The J18 performs on the display.

  • Page 32: J18 Control Descriptions And Operation

    Functional Overview J18 Control Descriptions and Operation Press the HOLD/RUN button to “freeze” measurements during normal operation. Press the HOLD/RUN button to resume measurements or to end differential measurements. Press the RANGE HI/LO button to change the sensitivity of the photometer when using single-channel sensors.

  • Page 33: J18 Display

    Functional Overview J18 Display The low battery icon The HOLD icon is The REF icon is flashes when the battery displayed when displayed when the J18 voltage is low. measurements have is in the store or See page 1–3. been interrupted. differential measurement mode.

  • Page 34: J18 Side Panel Connections

    Functional Overview J18 Side Panel Connections 9 to 16VDC 50mA MAX ANALOG OUTPUT RS232D Connect the optional The analog output output Connect the optional AC adapter here. samples the amplifier RS-232 cable here for data See page 1–5. output before the A-to-D logging to a computer.

  • Page 35: Tutorial

    Tutorial This section lists step-by-step instructions for storing and comparing color measurements. Conditions Before operating the photometer, it must meet the following conditions: Sensor head installed Power on Self-test completed without errors or low-battery indication Refer to the J1800 Series LumaColor Photometer Sensor Heads Technical Reference for specific turn-on procedures.

  • Page 36: Storing Measurements

    Tutorial Storing Measurements NOTE. The STORE button will only work with the J1810 sensor head. 1. Press the HOLD/RUN button to stop the measurement. See Figure 2–1. Figure 2–1: Measurement with HOLD 2. Press the DIFF/REF button to select the differential measure- ment mode.

  • Page 37: Recalling Stored Measurements

    Tutorial 3. Repeatedly press the DIFF/REF button to select the desired reference memory location. The reference location is shown on the top of the display. See Figure 2–2. Readings can be stored only in reference locations 1 to 10. Figure 2–2: Selecting a Reference Memory Position 4.

  • Page 38: Comparing Measurements

    Tutorial 5. Press the HOLD/RUN button again to return to the direct measurement mode. Comparing Measurements NOTE. The DIFF/REF button will only work with the J1810 sensor-head. Press the DIFF/REF button to enter the differential mode. Repeatedly press the DIFF/REF button to step to a reference memory location.

  • Page 39: Table 2-1: Factory Preset 6500 K White Values

    Tutorial Factory-stored reference values for video display white levels are stored in memory locations 12 to 19. Use these values to adjust displays to 6500 K white at standard luminance values. Refer to Table 2–1 for luminance values and memory locations. Table 2–1: Factory Preset 6500 K White Values Memory Location...
  • Page 40 Tutorial J18 Photometer Instruction Manual 2–10...
  • Page 41 Reference...

  • Page 43: Rs-232D Operation

    RS-232D Operation You can use the J18 LumaColor II Photometer’s RS-232D port to remotely control the photometer and to save measurement readings to a file on a computer. All of the functions of the front panel control can be duplicated through the RS-232D port. RS232D The RS-232D Port Figure 3–1: Location of the RS-232D Port...

  • Page 44: Rs-232 Pin Connections

    RS-232D Operation RS-232 Pin Connections An RS-232 cable is available as an optional accessory to the J18 (refer to Replaceable Parts for ordering information). This cable has a 3.5 mm connector for the J18, and a DB-9 female connector for connection to the computer.

  • Page 45: Syntax

    Syntax The data format for measurements consists of a units notation, followed by the floating-point measurement value. Values are displayed with four significant digits, and a one-digit exponent with an optional minus sign. For multiple values. See Figure 3–3. !NEW x = 0.100E0 y = 0.331E0 LUM = 34.65E–3 cd/m^2 Figure 3–3: Sample Measurement Message Each line is terminated by a carriage return and line feed (CR/LF).

  • Page 46: Table 3-2: Measurement Units

    Syntax Table 3–2 lists the abbreviations the J18 uses when reporting measurement units over the RS-232D interface. Table 3–2: Measurement Units Abbreviation Usage candelas cd/m^2 candelas/meter foot-candles foot-lamberts kelvins watts W/m^2 watts/meter W/m^2/sr watts/meter /steradian X, Y, Z 1931 CIE tristimulus values u‘, v‘...

  • Page 47: Table 3-3: J18 Command Syntax

    Syntax Table 3–3 summarizes the syntax conventions of the command set. Table 3–3: J18 Command Syntax Symbol Meaning Begins command. (All commands should be prefaced with an exclamation point.) {CR} Carriage return (ASCII 13); recognized as an end-of-com- mand delimiter. {LF} Line feed (ASCII 10);...
  • Page 48 Syntax J18 Photometer Instruction Manual 3–6...

  • Page 49: Commands

    Commands The J18 LumaColor II Photometer recognizes ten commands that duplicate the function of the front panel controls. These commands are summarized in Table 3–4. NOTE. The J18 is a case-sensitive device, so all RS-232 commands should be made in capital letters (upper-case), for example: !NEW. Table 3–4: J18 Command Set Command Function...
  • Page 50 Commands J18 Photometer Instruction Manual 3–8...

  • Page 51: Analog Output

    Analog Output The J18 features an uncalibrated analog output for use with auxillary equipment such as strip chart recorders and analog meters. The analog output is driven by the “Y” luminance channel. This is the same channel that is used for single-channel sensor heads. The analog output samples the J18 amplifier output before it goes to the D to A converter.

  • Page 52: Table 3-5: Analog Output Specifications

    Analog Output Table 3–5: Analog Output Specifications Characteristic Standard Connection 2.5 mm phone plug, center conductor positive (+) Time Constant 100 ms Output Level 0 to +5 VDC (typical) Output Impedance 100 k (typical) J18 Photometer Instruction Manual 3–10...

  • Page 53: Specifications

    Specifications...

  • Page 55: Table 4-1: Warranted Electrical Specifications

    Table 4–1: Warranted Electrical Specifications Characteristic Standard Accuracy 1% of reading 2 count (Excluding sensor nonlinearity) Emissions EN 50082-1 when used with Tektronix power supply and RS-232 cable. EMI Immunity EN-50082-1 ESD Immunity Up to 8 kV Table 4–2: Typical Electrical Specifications...

  • Page 56: Table 4-3: Warranted Environmental Specifications

    Specifications Table 4–3: Warranted Environmental Specifications Characteristic Standard Temperature Nonoperating: –55 C to +85 C Operating: –15 C to +55 C Per Tek Std 062–2847–00 Humidity Nonoperating: 97%, +30 C to +60 C Operating: 97%, +30 C to +55 C Table 4–4: Typical Mechanical Specifications Characteristic Standard...

  • Page 57: Table 4-5: Warranted Sensor Ranges

    Specifications Table 4–5: Warranted Sensor Ranges Sensor Range J1803 0.3 to 300,000 cd/m (nit) 0.1 to 100,000 fL J1805 0.01 mcd to 10 cd J1806 0.001 to 200 W/m J1810 0.001 to 0.999 xy and u’v’ coordinates (above 3 cd/m 0.3 to 1000 cd/m (nit) 0.1 to 300 fL...
  • Page 58 Specifications J18 Photometer Instruction Manual 4–4...
  • Page 59 WARNING The following servicing instructions are for use only by qualified personnel. To avoid injury, do not perform any servicing other than that stated in the operating instructions unless you are qualified to do so. Refer to all Safety Summaries before performing any service.

  • Page 61: Performance Verification

    Performance Verification...
  • Page 63 Performance Verification Performance verification procedures are included in the manual shipped with the J1800 series sensor-heads. If you are checking sensor-heads formerly used with a J17, the J17 verification procedure may be used. NOTE. The J1820 chromaticity sensor-head will not work with the J18.
  • Page 64 Performance Verification J18 Photometer Instruction Manual 5–2...

  • Page 65: Maintenance

    Maintenance...

  • Page 67: Service Strategy

    Service Strategy The J18 is user serviceable to the circuit-board level. Certain cosmetic parts and connectors may also be replaced by the customer. A list of replaceable parts is in the Replaceable Parts chapter. Basic Troubleshooting lists some operating conditions to check for if you believe the photometer or the sensor-head is not operating correctly.
  • Page 68 Service Strategy J18 Photometer Instruction Manual 6–2...

  • Page 69: Troubleshooting

    Troubleshooting If the J18 LumaColor II Photometer or one of the J1800 Series sensor heads does not appear to function correctly, the information in this section will help you isolate the problem. Basic Troubleshooting This section lists some common problems and their most likely causes.
  • Page 70 If measurements are still incorrect, the sensor head may require recalibration. Contact your Tektronix representative. Board-level Troubleshooting The two circuit boards in the J18 may be replaced. If the J18 does not function, you can use these procedures to isolate the problem to one of the boards.
  • Page 71 Troubleshooting The A1 Board Most functions of the J18 are located on the A1 board. Checking the Power Supply, later in this section, will allow you to determine whether there is a power supply problem. The A2 Display Board The A2 Display board is probably at fault if: segments of the display are missing the backlight does not operate To check the display, power on the J18 without a sensor head...

  • Page 72: Figure 6-1: Test Point Locations On The A1 Board

    Troubleshooting 4. Remove the five screws that attach the A1 board to the A2 board. 5. Gently pull the two boards apart, taking care not to bend the connector pins on the A1 board. 6. Connect the battery to the A1 board and turn on the power switch.

  • Page 73: Replaceable Parts

    Replaceable Parts...

  • Page 75: Parts Ordering Information

    Replacement parts are available from or through your local Tektronix, Inc. service center or representative. Changes to Tektronix instruments are sometimes made to accommo- date improved components as they become available and to give you the benefit of the latest circuit improvements. Therefore, when...
  • Page 76 Replaceable Parts Item Names In the Replaceable Parts List, an Item Name is separated from the description by a colon (:). Because of space limitations, an Item Name may sometimes appear as incomplete. For further Item Name identification, U.S. Federal Cataloging Handbook H6-1 can be used where possible.

  • Page 77: Figure 7-1: J18 Replaceable Parts

    Replaceable Parts Figure 7–1: J18 Replaceable Parts J18 Photometer Instruction Manual 7–3...

  • Page 78: Figure 7-2: J18 Optional Accessories

    Replaceable Parts Figure 7–2: J18 Optional Accessories J18 Photometer Instruction Manual 7–4...
  • Page 79 Replaceable Parts J18 Photometer Instruction Manual 7–5...
  • Page 80 Replaceable Parts J18 Photometer Instruction Manual 7–6...
  • Page 81 Replaceable Parts J18 Photometer Instruction Manual 7–7...
  • Page 82 Replaceable Parts J18 Photometer Instruction Manual 7–8...
  • Page 83 Replaceable Parts J18 Photometer Instruction Manual 7–9...
  • Page 84 Replaceable Parts J18 Photometer Instruction Manual 7–10...

  • Page 85: Appendices

    Appendices...

  • Page 87: Appendix A: Photometry And Radiometry Reference

    Appendix A: Photometry and Radiometry Reference This appendix summarizes convenient relationships and formulas used in photometry and radiometry. Photometric Relationships In photometry, the spectral sensitivity of the sensor is matched to the average human eye, with a peak at 555 nm. An isotropic light source (a source that emits light uniformly in all directions) of 12.6 lumens is 1 candela (1 candle power).

  • Page 88: Photometric Formulas

    Appendix A: Photometry and Radiometry Reference Photometric Formulas 10.764 footcandles (lumens meter 3.426 footlamberts nits (candela meter footcandles distance (in feet) candelas lux distance (in meters) candelas footcandles surface reflectance factor footlamberts Radiometric Relationships In radiometry, an ideal sensor has equal sensitivity to all wavelengths of light being measured.

  • Page 89: Radiometric Formulas

    Appendix A: Photometry and Radiometry Reference Radiometric Formulas watt cm 10000 watt meter watt meter distance (in meters) watt steradian A Note on the Relation of Photometric and Radiometric Data It is not possible to convert photometric units to radiometric units, or the reverse, except under precisely specified conditions.
  • Page 90 Appendix A: Photometry and Radiometry Reference J18 Photometer Instruction Manual A–4...

  • Page 91: Appendix B: Chromaticity Reference

    Appendix B: Chromaticity Reference The reference material in this appendix can help you categorize and understand chromaticity measurements taken using the J1810 Chro- maticity head. This appendix includes: The 1931 CIE Chromaticity diagram for x,y readings The 1976 CIE-UCS chromaticity diagram for u , v readings Spectral tristimulus (X, Y, Z) values for an equal spectral power source, in both graphical and tabular format.

  • Page 92: The 1931 Cie Chromaticity Diagram

    Appendix B: Chromaticity Reference The 1931 CIE Chromaticity Diagram The 1931 CIE chromaticity diagram, also known as a Kelly chart, is shown in Figure B–1. The diagram can be used to categorize chromaticity measurements expressed as x, y values. The x, y values are determined from the spectral tristimulus values (X, Y, Z), by the following equations: The main features of the 1931 CIE chromaticity diagram include:...

  • Page 93: Figure B-1: The 1931 Cie Chromaticity Diagram

    Appendix B: Chromaticity Reference .900 .800 .700 Greenish Yellow Yellowish Yellow .600 Green Yellow Green Yellowish Green Orange .500 Reddish Orange Bluish Orange .400 Green White Blue Pink Green .300 Purplish Purplish Greenish Pink Blue .200 Blue Purple Reddish Purple .100 Purple Purplish...

  • Page 94: Figure B-2: 1931 Cie Chromaticity Diagram Showing Color

    Appendix B: Chromaticity Reference Figure B–2 shows the Planckian locus on the 1931 CIE diagram. The numbers along this line indicate the color temperatures (in degrees Kelvin) for blackbody light sources. .900 .800 .700 .600 .500 2350 1900 2850 3500 1500 .400 4800...

  • Page 95: Figure B-3: Correlated Color Temperature Diagram

    Appendix B: Chromaticity Reference Figure B–3 shows selected isotemperature lines in the x,y coordinate system. A light source along one of the isotemperature lines will most nearly match the color temperature of a blackbody radiator indicated for that line. 0.500 2854 2500 2000 3000...

  • Page 96: The 1976 Cie-Ucs Chromaticity Diagram

    Appendix B: Chromaticity Reference The 1976 CIE-UCS Chromaticity Diagram The 1976 CIE-UCS (Uniform Chromaticity Scale) diagram, shown in Figure B–4, can be used to categorize chromaticity measurements expressed as u , v values. u and v are related to the x and y values of the 1931 CIE chromaticity diagram by the following equations: This diagram is similar to the 1931 CIE chromaticity diagram except for the following:...

  • Page 97: Figure B-4: 1976 Cie-Ucs Chromaticity Diagram

    Appendix B: Chromaticity Reference Greenish Orange Yellowish Yellow Yellowish Yellow Yellow Reddish Green Green Pink Orange Yellow Orange .600 Green .500 Pink Bluish White Green Purplish Purplish Pink .400 Greenish Blue Reddish Purple .300 Blue Purple .200 .100 .000 .100 .200 .300 .400...

  • Page 98: Spectral Tristimulus Values

    Appendix B: Chromaticity Reference Spectral Tristimulus Values Figure B–5 shows the spectral tristimulus (XYZ) values for a light source of equal spectral power. Table B–1 lists the same data in tabular format. z( ) x( ) y( ) Wavelength (nm) Figure B–5: Spectral Tristimulus Values for Equal Spectral Power Source (CIE 1931 Standard 2 Observer) Note that y( ) is also the photopic curve that represents the relative...

  • Page 99: Table B-1: Spectral Tristimulus Values For Equal Spectral Power

    Appendix B: Chromaticity Reference Table B–1: Spectral Tristimulus Values for Equal Spectral Power Source (CIE 1931 Standard 2 Observer) Wavelength (nm) x( ) y( ) z( ) 0.0014 0.0000 0.0065 0.0022 0.0001 0.0105 0.0042 0.0001 0.0201 0.0076 0.0002 0.0362 0.0143 0.0004 0.0679 0.0232...
  • Page 100 Appendix B: Chromaticity Reference Table B–1: Spectral Tristimulus Values for Equal Spectral Power Source (CIE 1931 Standard 2 Observer) (Cont.) Wavelength (nm) x( ) y( ) z( ) 0.0024 0.4073 0.2123 0.0093 0.5030 0.1582 0.0291 0.6082 0.1117 0.0633 0.7100 0.0782 0.1096 0.7932 0.0573...
  • Page 101 Appendix B: Chromaticity Reference Table B–1: Spectral Tristimulus Values for Equal Spectral Power Source (CIE 1931 Standard 2 Observer) (Cont.) Wavelength (nm) x( ) y( ) z( ) 0.6424 0.2650 0.0000 0.5419 0.2170 0.0000 0.4479 0.1750 0.0000 0.3608 0.1382 0.0000 0.2835 0.1070 0.0000...
  • Page 102 Appendix B: Chromaticity Reference Table B–1: Spectral Tristimulus Values for Equal Spectral Power Source (CIE 1931 Standard 2 Observer) (Cont.) Wavelength (nm) x( ) y( ) z( ) 0.0002 0.0001 0.0000 0.0002 0.0001 0.0000 0.0001 0.0000 0.0000 0.0001 0.0000 0.0000 0.0001 0.0000 0.0000...

  • Page 103: Glossary And Index

    Glossary and Index...
  • Page 105 Glossary Area Source A light source of large angular size. Blackbody (Planckian Radiator) A thermal light source having light produced by heating. The intensity and color of a blackbody are primarily dependent on operating temperature. Chromaticity The quality of color. Based on wavelength distribution and purity.
  • Page 106 Glossary Luminance The amount of light emitted or scattered by a surface. Usually measured in candelas/meter (nits)or foot-lamberts with a sensor spectrally matched to the average human eye. Luminous Flux The total light from a source, measured in lumens with a sensor spectrally matched to the average human eye.
  • Page 107 Glossary Radiometry The measurement of radiant power. A radiometric sensor is equally sensitive to all wavelengths present in the light being measured. Reflectance Factor The ratio of reflected light to received light on a surface. Tristimulus Values (X,Y,Z) The amounts of each of three color primaries required to match the color of a light.
  • Page 108 Glossary J18 Photometer Instruction Manual Glossary–4...
  • Page 109 Index Accuracy, conditions affecting, 6–3 DIFF REF, 2–2, 2–7, 2–8 Adapter, power, 1–5 ALT DISPLAY, 2–2 Analog output location, 2–4, 3–9 Features, 1–1 specifications, 3–10 Firmware version, 1–8 Front-panel, 2–1 Functional check, 1–7 Backlight, 2–1 Battery low battery warning, 1–3, 2–3 HOLD icon, 2–3 replacing, 1–4 HOLD/RUN, 2–2...
  • Page 110 Index measurement abbreviations, 3–4 message format, 3–3 Low battery warning, 1–3 parameters, 3–1 pin connections, 3–2 syntax, 3–5 Measurements comparing, 2–8 recalling, 2–7 Self-Test, 1–7 storing, 2–6 Sensor auto-zero, 1–9 cover, 1–7 missing, 1–10 not recognized, 1–10 Packaging, 1–2 Shipping, packaging for, 1–2 Performance verification, 5–1 Specifications Photometry...
  • Page 111 Index XYZ values, B–8 J18 Photometer Instruction Manual Index–3...
  • Page 112 Index J18 Photometer Instruction Manual Index–4...

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