Takahashi© was the first manufacturer to make apochromatic telescopes using a fluorite element in the objective. Since the first 90mm fluorite apochromat was introduced in 1977, Takahashi© has developed an extensive line of apochromats using doublet and triplet objectives. The objective lenses of these refractors use man-made fluorite crystal which is made from natural calcium fluorite (CaF2). Now as a result of a production breakthrough which permits the fluorite crystal to be completely hard multi-coated, Takahashi© has been able to finally redesign its fluorite FC series to produce the FS series. The new design places the fluorite element in front of the objective to achieve the maximum color correction and light transmission.