Taqi al-Din was an influential 16th century polymath from Damascus who made significant contributions across many fields including astronomy, physics, engineering, and optics. He served as the official astronomer for the Ottoman Sultan Selim II. Some of his key inventions and achievements included building the largest astronomical observatory of its time in Istanbul, developing highly accurate astronomical instruments and clocks including the first to measure time in seconds, and publishing works describing early concepts of steam power and telescopes. His extensive writings on optics significantly advanced the scientific understanding of light, reflection, refraction, and the formation of color.

1. Taqi al-Din (1526–1585)
He was born in 1521 in Damascus, Syria, and was educated in Cairo, Egypt.
He became the official astronomer for Ottoman Sultan Selim II.
He was a scientist, astronomer, astrologer, engineer, inventor, clockmaker,
watchmaker, physicist, mathematician, botanist, zoologist, pharmacist, physician,
Islamic judge, philosopher, theologian and Madrasah teacher.
He was the author of more than 90 books on a wide variety of subjects, One of his
books described the workings of a rudimentary steam engine and steam turbine in
1551, predating the more famous discovery of steam power by Giovanni Branca in
1629.
His inventions include a variety of accurate clocks including the
first mechanical alarm clock,
the first spring-powered astronomical clock,
the first watch measured in minutes, and
the first clocks measured in minutes and seconds.

2. Taqi al-Din builds the Istanbul observatory of al-Din, the largest
astronomical observatory in its time, with the patronage of the Ottoman
Sultan Murad III.
At the Istanbul observatory of al-Din, Taqi al-Din carries out astronomical
observations.
He produces a zij (named Unbored Pearl) and astronomical catalogues that
are more accurate than those of his contemporaries, Tycho Brahe and
Nicolaus Copernicus.
Taqi al-Din is able to achieve this with his new invention of the
"observational clock", which he describes as "a mechanical clock with three
dials which show the hours, the minutes, and the seconds."
This is the first clock to measure time in seconds, and he uses it for
astronomical purposes, specifically for measuring the right ascension of the
stars.
This is considered one of the most important innovations in 16th century
practical astronomy, as previous clocks were not accurate enough to be
used for astronomical purposes.

3. He further improves his observational clock, using only one dial to represent
the hours, minutes and seconds, describing it as "a mechanical clock with a dial
showing the hours, minutes and seconds and we divided every minute into five
seconds."
Taqi al-Din is also the first astronomer to employ a decimal point notation in
his observations rather than the sexagesimal fractions used by his
contemporaries and predecessors.
Taqi al-Din was the first mathematician to extract the precise value of Sin 1°.
He also invented some astronomical instruments as well as one of the
first spring-powered pocket watches.
Taqi al-Din invents a rudimentary telescope,
Taqi al-Din publishes The Brightest Stars for the Construction of Mechanical
Clocks, which describes the first mechanical alarm clock, the first spring-
powered astronomical clock, and the first clock and mechanical watch to first
measure time in minutes.
Taqi al-Din invents a 'Monobloc' pump with a six cylinder engine.
It was a hydropowered water-raising machine incorporating valves, suction and
delivery pipes, piston rods with lead weights, trip levers with pin joints, and
cams on the axle of a water-driven scoop-wheel.

4. Taqi al-Din’s work in the field of optics is very extensive, his momentous treatise;
Kitab Nūr hadaqat al-ibsār wa-nūr haqīqat al-anzār
(Light of the Pupil of Vision and the Light of the Truth of the Sights)
was written in three volumes.
The first volume deals with vision, which includes properties of light, the structure
of the eye and many other related subject.
The second contains experimental investigations on lights reflection, and
The third deals with refraction of light, including global refraction, and the relation
between light and color.
He provides the first satisfactory explanation for the formation of color, clearly
stating that color is formed as a result of reflection and refraction of light, two
centuries before Isaac Newton.
The method of construction of a rudimentary telescope can also be found in his
treatise. It is a comprehensive book on optics.