Abbe Value

Definition of the Abbe Dispersion Value
(Chromatic Aberration) ©

One very important property of an optical lens material is the Abbe value.  It is a measure of the degree to which light is dispersed or separated when passing through a lens.  The dispersion occurs at any time when white light is broken into its component colors.  If the Abbe value is too low, then the light dispersion will cause chromatic aberration which appears in one's vision to be like a rainbow around viewed objects especially noticed around light sources.

The higher the Abbe value, the better the peripheral optics will be.  The lower the Abbe value, the more chromatic aberration will be a characteristic of that lens.  Human eyes can not detect the chromatic aberration if the Abbe number is above 40.

Many plastic materials have Abbe values of roughly 58.  Most high index plastic type materials have a lower Abbe value, some as low as 30.  In mineral glass of an index 1.80 or 1.90 the Abbe value can be even lower.  These low level Abbe values make for very difficult night vision.

You may be interested to know that the naked human eye lens exhibits chromatic aberration.  Fortunately, a yellow pigment in the fovea called the macula lutea helps to protect us from this problem.  Yellow pigments absorb blue light.

The following information could be very helpful in making a decision about which lens type should be chosen for the next purchase.



Table Of Abbe Value For Various Materials

Index of Refraction

Abbe Value

Specific Gravity

Plastic (1.50)
58
1.32
Trivex (1.53)
43
1.11
Essilor (1.56)
37
1.36
Hoya (1.56)
41
1.20
Polycarbonate (1.59)
30
1.21
Essilor (1.60)
36
1.34
Hoya (1.60)
42
1.34
Shamir (1.60)
42
Signet (1.60)
34
1.34
Sola (1.60)
42
1.34
Varilux (1.60)
36
1.34
Optima (1.66)
32
1.36
Pentax (1.66)
32
1.35
Hoya (1.67)
31
1.35
Essilor (1.67)
32
1.35
Shamir (1.67)
31
   
Seiko (1.67)
32
1.36
Kodak (1.67)
32
1.35
Hoya (1.70)
36
1.41
Seiko (1.74)
32
1.47
Essilor (1.74)
33
1.46



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