I want to understand what is way to realize such concentric rings in illustrator more simply?
For a graphic like this I prefer to use the Polar Grid Tool, which is located in the sub-menu of the Line Segment Tool:
- Set the stroke to black with no fill and make it 3pt in thickness for the purposes of this explanation:
- Select the Polar Grid Tool and click on the artboard to bring up the Polar Grid Tool Options Menu:
For this instance, let's use the settings in the image above. Click OK to apply settings. The results should be as follows:
- Use the Selection Tool to select the shape. Open the Stroke Panel and tick the Dashed Line, Round Caps and the Align Dashes to corners and path ends options. Additionally, set the Dash to 0pt and the Gap to 6pt:
- Add the center dot. Create a 3px by 3px circle with the Ellipse Tool and center it in the resulting space:
As with many things in Illustrator, there are many ways to perform the same task. I find this option to be the most forgiving when it comes to making revisions since you only need to edit a few settings in easily accessible places. Hope it helps!
This is not quite the same, but it should get you moving in the right direction...
First, create a circle with a dashed stroke, using settings that are something like those in the following screens shot:
Next, duplicate the circle and then enlarge the duplicate, keeping the circles on the same centre point. Then use the blend tool to create a blend between the inner and outer circles. I used a fixed distance blend, but you might prefer a specified number of steps. The result will look something like this:
You can adjust the density of the dots and the circles by tweaking the gap setting of the dashed stroke and the spacing of the blend. To adjust the size of the dots, just change the Weight of the strokes. If you want to fill in the centre, just reduce the size of the inner circle.
Like I said, not exactly the same as your example, but not bad for 5 minutes!