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Mitutoyo Institute of Metrology / Mitutoyo America Corporation / Chicago USA

Nobuo Suga

Precision Length

Measurement to

Improve Quality and Productivity

in Manufacturing


A B

Comparison

Measurement

“Known” “Unknown”


Artifact Standard

1: End Standard

2: Line Standard Gage Blocks

Glass Scales


Carl E. Johansson (1864-1943)

“The Master of Measurement,” also known as “the most precise man”reached 1µm at the turn of the last century


Johansson’s Gage Block Set patented in 1911


µ


633 633 633 633

Gage Block

L End Standard


633 633 633 633

L

End Standard

Zero Cera Block


633 633 633 633

L

End Standard

Zero Cera Block


633 633 633 633

L

End Standard

Zero Cera Block


633 nm

Wavelength of Helium-Neon Laser (and Fringe Lines)


Test Model No. 1 632 991 382 fm

No. 2 632 991 412 fm

No. 3 632 991 379 fm

No. 4 632 991 331 fm

No. 5 632 991 388 fm

No. 6 632 991 381 fm

633 633 633 633 Wavelength of randomly selected

Laser Interferometers tested by Mitutoyo (was accurate within one picometer)

Nano

Pico Femto


Is traceability to NIST required?


Measurement Uncertainty (U) @ NIST, Washington, DC

50 mm End Standard = 31 nm

50 mm Line Standard = 8 nm

Temperature controlled = 0.005 C

°

In comparison, JIS standard “0.5” Grade = 0.5 C

°


End Standard

G a g e B l o c k

0.577L

(Airy Point)

µ

Narrow Range accuracy calibrated at NIST for 50 mm was 0.1 m

50 mm

µ

Sealed Chamber: Temperature kept at: 0.005 C

°

Calibrated at NIST

0.05 C °


m International System of Units (SI)

299 792 4xx m/s

299 910 xxx m/s

C = 299 792 458 m/s

1879 Michelson

1953 Michelson

1983 CIPM

(C = Speed of light in vacuum)


s

m Unit of Length

Unit of Time

Accuracy of 1 Second: NIST–F2 Model (under development now)

0.000 000 000 000 000 001 1 Second error =Ten to the power of negative 18

SI


Standard Temperature

23 25 20

°

C °

°

C

C

68 °

F At the turn of the last century, Johansson

calibrated his gage blocks at 20 degree C,

which was then the average machine shops

temperature in northern Europe.


Standard Temperature

20

0.01

(in degree C)

29.76 Triple Point of

water Standard

Temperature

Melting point

of Gallium

International Temperature Scale (IT-90)


Room Temperature

20

5

(in degree C)

35

The Definition of so-called “Room Temperature”

in accordance with JIS Standard Z 8703


G a g e B l o c k

0.577L

(Airy Point)

Sir George Airy (1801-1892) Astronomer at Greenwich Observation Laboratory

End Standard

ZERO CERA BLOCK

“Step Gage” (Check Master) to calibrate CMMs


Temperature is raised and lowered to study the effect of expansion

“The most accurate man is the man with the most accurate thermometer.” Ted Doiron, Metrologist, NIST


Artifact Standard NMC Seminar in Singapore

Thank you,

Yours truly,

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