How Was the Telescope Improved?
The improvement of the telescope to the powerful instrument of our time was a long gradual process involving many men and many centuries. It was all based on the improvement of the lenses. Galileo’s telescope was quite simple. It had two lenses in a lead tube.
In 1610, Johannes Kepler of Germany used a more complicated lens system, which gave higher magnification. From that Huygens, of Holland, learned to grind lenses that would focus more accurately and made some that brought the rays of the sun down to a flaming pin point.
Isaac Newton, the great British physicist, after spending much time in designing color-corrected lenses, made a great improvement on the astronomical telescope. There had been experimentation with curved mirrors that gathered the reflection of an image and focused it. Newton used this technique in what is now known as the reflecting telescope.
The mirror received the distant image and sent it through a system of lenses for magnification. This device, the reflecting telescope, is the one we use today for most astronomical observation.
The modern version is essentially the same as Newton’s in principle. The reflecting telescope has the highest power and allows us to see distant galaxies that are millions of light years away.