This type of chart is called Point & Figure charts. It's mentioned in many books out there, even in John Murphy book about technical analysis of the financial markets. A good source to start with is here:
StockCharts.com - Point & Figure Charts
and here are some of the chart patterns you can look for, to make your trading decisions:
StockCharts.com - P&F Pattern Alerts
If you also take trendlines, which have (almost) alway 45 degrees in Point & Figure charts, you get a good overview of the market and can filter out some bad trades. Beside that, I have included a moving average, which can also be applied to P&F charts. A sell signal above the MA will be ignored, a buy below the MA also.
And you're right, the P&F chart acts kind of like a filter. Only 'big' price movements will be plotted on the chart. How big this move is, is defined by your box size - in my previous screenshot it was a box size of 2 ticks. And a reversal of the price movement (changing from rising prices, symbolized by X's, to falling prices, symbolized by O's) will only be drawn, after a given reversal amount. In my case this was also 2 - so only if price falls 2 times the box size (=4 ticks), a new column will be plotted.
So P&F charts are solely based on price movements and don't take the time into consideration - the only thing you know about time is: on the right hand side of the chart happend later than on the left hand side.
By adjusting box size and reversal amount, you can make the chart react more sensible to price movements or only take big moves into account, if you use bigger box sizes and reversal amounts. This also defines your time horizon for the trade. A 2 x 2 setup can be used for daytrading, while a box size of 10 ticks would result in a lower trading frequency and you would keep positions opened for a longer period.
For those of you who are interested, I have attached the current chart with 2 ticks, 5 and 10 ticks box size. Reversal is still 2 boxes - though a reversal of 3 is the common standard. But a reversal of 2 gives more signals and allows tighter stop losses (I put the initial stop loss right below a given signal).