I.
TELEVISIONHISTORY
II. Early inventions
A.
Julius Plucker – 1858
1. His tube
a) Tube with
electrodes at either end
b) Sucked out the
air
2. Result
a) Fed electricity
into the tube
b) Excited the
electrons
c) Caused a
florescent glow on the walls of the tube
d) The flow of
electrons could be moved by a magnet
B.
Sir William Crooks – 1875
1. His tube
a) Was used for
everything from X-rays to nuclear power experiments
b) A major factor
in the invention of television
c) Much like Plucker’s tube
d) Crooks added a
gate at one end
2. Result
a) Gate forced
electrons into a beam instead of just diffusing them throughout the tube
b) Beam of
electrons went from one electrode to the other
c) A magnet made
the beam bend in the direction of the magnet
d) Thus, a beam of
electrons could be controlled by an electromagnet, a basic necessity for
television
C.
Karl Braun – 1897
1. Created the cathode ray tube
a) Based on the
work of Plucker and Crooks
b) Vacuum tube
c) Electron gun
(the diode of the circuit) in one end
(1)
Shot
out a beam of electrons
(2)
Sent
to a plate, the anode of the circuit
d) Electromagnets
bend the beam of electrons
e) Beam hits a
screen painted with florescent paint at the other end of the tube from the
electron gun
(1)
The
beam makes the screen glow where the beam hits
(2)
Moving
the beam can create glowing lines on the screen
D.
Backwards in time
1. Danish researchers in 1873
a) Discovered that
the electrical resistance of selenium varies in proportion to the intensity of
the light shining on it
b) Can transform
light into electrical signals
E.
Proposals to transmit pictures by wire
1. G.R. Carey – 1875
a) First attempt
to transmit a picture from a camera to a receiver
(1)
To
capture the image
(a) A mosaic of
selenium cells
(b) Each cell
connected by wires to a battery and an electric lamp
(c) One lamp for
each cell
(d) Cell reacts to
light falling on it and sends an electric current
(e) Created an
electronic version of a picture from a camera
(2)
To
receive the image
(a) Current from
the selenium cells sent down wire to electric lamps
(b) Lamps would
light up in direct proportion of the amount of current
b) Idea wasn’t
practical since it would need millions of selenium cells and lamps, each with
its own wire, to produce a clear picture
(1)
Carey
considered scanning the image to reduce the number of cells
2. Shelford Bidwell – 1881
a) Scanning device
(1)
Single
selenium cell in a camera obscura
(2)
Motor
drive moves the box up and down rapidly across the plane of the image
(3)
Device
worked but was limited in speed
b) Maurice leBlanc suggested using an oscillating mirror to reflect
the image onto a fixed selenium cell
3. Paul Nipkow – 1884
a) Created the
mechanical “television”
(1)
Simplest
and most workable of the scanning systems proposed
(2)
An
object is illuminated
(3)
Reflected
light from the object goes through the holes cut in a spiral in a spinning disk
(4)
Light
falls on a selenium cell
(5)
Current
from the cell sent down a wire to a lamp
(6)
Light
from the lamp shines through a second identical disk of holes
(a) recreating the light from the illuminated object
(b) light shines on a screen
(7)
each
spin of the disk equals one frame
b) quality of picture was bad
(1)
18
lines per frame compared to todays 525 (1080 in HD)
c) Proved the
principle of scanning as viable
F.
The creation of actual television (sight at a
distance)
1. Nothing happened for 20 years
2. New method – electronic instead of mechanical
a) Boris Rosing of Russia
– 1902
(1)
Used
Braun’s cathode ray tube for image reproduction
(2)
1907
– mechanically produced picture viewed on a cathode
ray tube in sync with the sending signal
(3)
Arrested
by Stalin and sent to Siberia
b) Archibald
Campbell-Swinton – 1908
(1)
First
to suggest using a cathode ray tube at both ends of the system
c) A Sinding-Larsen – 1911
(1)
Suggested
using radio instead of wires as a carrier for the picture signals
d) All the
concepts necessary for TV as we know it are in place
3. World War I interrupts
4. Charles Francis Jenkins – 1923
a) Demonstrates his
mechanical TV in the US
b) Used Nipkow’s disk system
5. John Baird – 1923
a) Demonstrates
his mechanical TV in England
b) First to
televise a face and a moving object
c) Used Nipkow disc and was crude
6. All this activity drew the attention of big
corporations
a) Started major
development programs
(1)
Building
labs
(2)
Hiring
researchers
(3)
Dumping
in lots of money
b) All came up
with mechanical TVs like Nipkow’s
(1)
Up
to 30 line scans
(2)
Pictures
still sucked
(3)
Disks
up to 4 feet across were unpractical
(a) TV was 50”
(b) Screen was 4”
7. Vladimir Zworykin
a) Boris Rosing’s student
b) Apparent patent
for his iconoscope in 1923
(1)
A
cathode ray tube
(2)
Could
pick up images and convert them to electrical signals
(3)
The
first camera tube
(4)
How
it worked
(a) Picture focused
on photosensitive mosaic mounted in the tube
(b) Mosaic scanned
line by line by an electron beam, releasing a small electric charge from each photoelement
(c) Speed of the
beam and the number of lines scanned no longer limited by mechanical
considerations
c) Created his
kinescope in 1929
(1)
A
vastly improved cathode ray picture tube
(2)
Now
the entire system is electronic
8. Philo Farnsworth
a) In 1927 came up
with the same ideas as Zworykin
9. Who invented TV – Zworykin or Farnsworth?
a) Zworykin
applied for an iconoscope patent in 1923, but it wasn’t granted until 1938
b) Farnsworth
challenged Zworykin’s patent in 1934 and won
(1)
Zworykin
had no evidence that he actually invented a device in 1923 that worked, only
his word
(2)
Zworykin’s
working models only appeared after he visited Farnsworth’s lab in 1930
c) On the basis of
the evidence
(1)
Farnsworth
is the “Father of Television”
(2)
Zworykin
was the improver for RCA
d) RCA
(1)
Zworykin
worked for RCA
(2)
David
Sarnoff
(a) Ran RCA
(b) Thought only
RCA should be a force in radio and television
(i) Own all the
patents
(ii) Have all the
credit
(iii) Thought
that RCA should “collect patent royalties, not pay them.”
G.
Television enters the market
1. Scanning lines increase in number
a) 1930 – 60 lines
b) 1941 – 525
lines
c) Resolution
vastly improved
2. 1939 New York World’s Fair
a) RCA introduces
television to the public for sale
(1)
Had
441 lines of resolution
(2)
Other
companies complained
(3)
FCC
(a) Rescinded
approval for commercial television
(b) An industry
committee reviewed standards for manufacture
(i) Approved most
of RCA’s standards
(ii) Raised the
number of scan lines to 525
(c) Approved the
standards and approved commercial TV
b) Then World War
II happened
3. 1946 – RCA introduces the “630”
a) 10” screen
b) Improved performaces
c) RCA gave other
companies the plans to stimulate production and demand
d) Market exploded
(1)
New
stations came on the air quickly
(a) Interference
problems just like with radio
(b) FCC froze new
station construction for a time
(2)
1946
– 6,000 sets in use
(3)
1952
– 22 million sets in use
4. What was on?
a) Radio with
pictures
(1)
Visuals
grab and hold attention in way radio couldn’t even come close to
(2)
It
didn’t matter what was being shown, only that it was
(3)
Novelty
quickly palled
b) Programming
(1)
All
TV programming came out of New York
studios
(a) Programs had to
fit in the studios
(b) Needed the
bright lights
(c) Shows were sent
out on the air live
(i) Sitcoms
(a) I Remember Mama
(b) Mr. Peepers
(ii) Dramas
(a) Playhouse 90
(b) Armstrong Circle Theatre
(iii) Comedy-variety
shows
(a) Your Show of Shows
(b) Texaco Star Theatre
(2)
TV
completely changed by I LOVE LUCY and Desi Arnaz
(a) Arnaz and his wife Lucille Ball wanted
to do a sitcom
(i) Wanted to live
in California
(ii) Wanted to
perform the show in front of a studio audience
(iii) Could do
neither of these things in New York
(b) Arnaz decided to film the show instead
of do it live
(i) Invented the 3
camera technique
(a) 3 cameras film the entire show at the same
time
(b) The 3 films are edited to create the actual
show
(c) Film sent to New York to be broadcast
(ii) Fallout from Arnaz’ idea
(a) Everyone wanted to film their shows
(b) Hollywood studios had all the cameras and sound
stages needed
(c) Hollywood now loves TV instead of hating it
(d) The TV industry moves from New
York to California
(e) Invention of the rerun
5. The next step – color TV
a) CBS in 1939
(1)
Had
a color TV system
(a) A wheel with 3
color filters rapidly rotates in front of the camera lens
(b) A similar wheel
is used in the receiver
(c) The problems
(i) the system is
mechanical
(ii) could get out of
synchronization
b) RCA in 1949
(1)
An
electronic color system
(a) 3 separate
pickup tubes in the camera, one for each primary color
(b) 3 kinescopes
(one for each color) in the receiver
(c) Required exact
– and hard to maintain – alignment
(d) Advantage over
CBS’s color wheel system
(i) Compatiblewith existing TVs
(ii) B&W TV
could get a good B&W picture
c) FCC gave
approval to the CBS system
(1)
RCA
sued, but lost
(2)
CBS
went on the air with color in 1950
(a) Nobody went
along
(i) Didn’t like
the idea of a color wheel in every set
(ii) Wanted
backward compatibility
(iii) RCA developed
the tri-color kinescope
(a) Only one tube instead of three hard to align
tubes
(b) CBS soon gave
up
d) National
Television Standards Committee (NTSC)
(1)
Recommended
a set of standards for color TV
(2)
Dec.
17, 1953 – FCC approves the start of color TV broadcasting based on NTSC
standards
e) NBC started
broadcasting in color
f)
RCA started selling cameras a transmitting
equipment to studios and color TVs to the public
g) Color TV didn’t
explode the way B&W had earlier
(1)
A
matter of money
(a) Producing shows
in color cost a lot more
(i) Only a few
color sets in use
(ii) Sponsors were
reluctant to pay the extra cost
(b) People were
reluctant to pay for a color TV when there were so few color shows
(2)
RCA
pumped in lots of money
(a) Promotion of
color TV
(b) Subsidized
color production
(c) By 1962 about a
million sets in use
(i) Enough for
sponsors to be willing to pay the extra cost
h) 1965 – 5
million sets in use and all networks had gone to full-color
i)
1970 – 37 million sets in use
H.
Basic system had stayed the same since 1953
1. Big changes in sets and telecasting equipment
a) Cameras smaller
b) TVs bigger
c) Cable and
satellite has changed the way we get TV
d) Digital has
replaced analog