Television Tokyo has prepared the following production guidelines in the interest of minimizing the risks of viewer exposure to harmful stimuli. The production and broadcasting of animation conducted on the basis of a firm awareness of these guidelines will eliminate almost all risks emerging from such programs.

1. Avoid use of more than one light flash per each one-third second(8 frames for film, 10 frames for television).

2. Because sudden cut changes or swift image changes will also cause the same impact as light flashes, avoid their use in excess of one such change per each one-third second.

3. Flashes and cut changes using the color "isolated red" will also be dangerous. However, there are no problems with color combinations which exclude isolated red when the luminance (brightness) is at the same level.

4. As a general rule, it is desirable to avoid use of systematic patterns (strips, bars, spirals, dart boards, etc.) with varying luminance levels. Patterns which reverse are the most provocative, but those which drift are not provocative.

According to Professor Harding or the U.K., an accepted authority on research into spasms caused by light hypersensitivity; "As long as the television itself is used as a medium to send out images via light changes, it will be impossible to totally eliminate the risk of symptoms occurring as a result of light stimulation."


ƒOne Light Flash per Each One-Third Second, and the Dangers„

@@@ While it is known that flickering, flashing, or other image effects on television screens have the potential to abnormal responses in the human brain, the degree of this danger varies widely by the speed of the flashing light. If the rate of flashing is held to less than one flash per each one-third second, the threat of light hypersensitivity seizures caused by that program can be reduced by about 97 percent.
¨@ One light flash per each one-third second is equivalent to one flight flash per eight frames during filming. The insertion projections per one frame of film widely used to date were equivalent to 12Hz ( 12 light flashes per second, 4 flashes per one-third-second), placing them in an extremely risky zone.
Of the people for which this has the potential to trigger a light hypersensitivity seizures, 78 percent will suffer abnormalities in their brain waves. Meanwhile, 5 percent will suffer reactions at 4Hz ( 4 flashes per second, 1.3 flashes per each one-third second ), 31 percent at 7Hz and 65 percent at 10Hz, with the reaction rate thus expanding in accelerated fashion along with the increase in Hz.

@@@The same type of caution is also required for sudden cut changes or quickly changing images, as they will have the same impact as light flashes.
@@@ Production checks must be performed on the basis of ample awareness of the dangers of such light flashes, and we have presented specific application examples below.

ƒDanger of Systematic Patterns with Different Luminance Levels„

@@@ Systematic patterns with different luminance levels, ( strips, bars, dart boards, etc.) harbor the same type of danger as light flashes. The most dangerous example is repetitive pattern reversals, followed by still images. The impact is said to be limited for objects which flow in a set direction and can be followed by the eye.