No one's answering me
...
In my experience of this forum, the most likely reason is that no-one here knows.
Can someone please tell me if my thinking is correct for working out max intensity I can push a 7 segment display based on peak forward current, duty cycle and pulse width (also refer attached specification sheet for this display). I'm really stuck...
I'm not sure you are even asking the right question.
I would phrase the question like this:
"We know the max continuous current is 30mA.
We know the max current is 160mA with pulse width 0.1ms and 1/10 duty cycle
What is the max current at pulse width 2ms and 1/4 duty cycle?"
And one answer you might get from the forum would be "if maximum brightness is really so important, don't multiplex".
I think its all to do with heat dissipation. The higher the current, the faster you are heating the leds. The temperature they reach depends on the length of the pulse, what temperature they were at the start of the pulse, and how fast they loose heat during the pulse. The temperature at the start of the pulse depends on what rate they cool. The rate at which they cool depends on the temperature at any instant. Its all horribly complicated.
But every time the led heats up and cools again, it looses a tiny part of its life. The hotter it gets, the larger that part of life is lost.
My advice would be that if you are building something for you own use, you can afford to push the limits. If you are designing something to be mass-manufactured and sold, you have to be much more conservative if you can't get a definitive answer to your question.
If it were me, I would go to maybe double the max continuous current with a 2ms pulse and 1/4 duty cycle, and be prepared for the possible consequences, but take comfort in the knowledge that the manufacturer's data sheet figures will be conservative.