Is that the 1.67 high index lenses wouldn't be any thicker than a 1.74 lens?

[San Elizario]

I just ordered some glasses from Specsavers and was told the 1.74 high index lenses wouldn't be any thinner than a 1.67 lens. Is that right? I have some 1.74 from another opticians and they are pretty thin. My eyes are +5.75 & +4.75.

[Boy River]

It is a fact that different index lenses have different thickness, and usually is a visible difference.your type is thicker in the middle and thinner on the edge. Maybe it is harder to observe the different index thickness, but it depends on how big the frame is.

[Glyndon]

Although in your condition, I recommend larger frame for a thinner lens on the edge, so a 1.74 lens would be thinner. There is no way that two different index lenses to be the same thickness. Maybe is not a big difference like between 1.5 and 1.67, but the 1.74 is thinner for sure than 1.67.