Creating a halftone in Illustrator takes a few steps and the effects are quite cool. This takes a halftone effect, the Image Trace panel and the 3D effect to create these super cool looking vector creations.
Start with a circle.
Open the Gradient panel under the Window Menu.
Click on the fill icon and select the radial fill from the 3 gradient options.
Double click on the black dot on the gradient slider and set the black to 80% black.
Radial gradient from white on the edge to 80% black in the middle.
Under the Effect Menu, choose Pixelate, Color Halftone. Set the Max radius to a higher number to get larger dots. Set each channel to the same angle, here I set it at 45°.
This is the result.
To edit the halftone dot size, double click on the Color Halftone Effect in the Appearance Panel.
Select the halftone pattern and choose Object>Expand to turn the effect into an image.
Open the Image Trace panel from the Window Menu. Set the mode to Black and White, threshold to the middle, Paths at HIGH, Corners at LESS, Noise at 1, Uncheck Snap Curves to Lines, Check Ignore White.
To turn the image into actual shapes after the Image Trace you have to Expand the shape. Choose Expand from the Control bar or Expand from the Properties Panel.
Select the newly expanded shape and drag it into the Symbols Panel and add it as a Dynamic Symbol for later use.
Create a circle to make it into a sphere.
Use the Direct Selection Tool to click on the left side and delete it, leaving a half circle
Choose Effect, 3D, Revolve. This will take the half circle and revolve it into a sphere. Click on the Map Art… Button.
To map the halftone to the sphere, choose from the Symbol dropdown menu and choose the Sphere symbol that we just added. The only type of artwork that can be mapped has to be a Symbol.
Move the symbol to the area in white which is the area you see on the sphere. Gray areas are the ones we don't see on the sphere. Scale the symbol up or down to fit. Click on the Invisible geometry button to make the sphere invisible. Click OK
This is how the symbol of the halftone looks when mapped to the invisible sphere.
To make a line into a halftone, create a line.
In the gradient panel, click on the stroke icon the click on the linear gradient.
There are 3 types of gradient strokes, the first one sets the stroke from one end to another.
The 3rd option sets the stroke to on the width of the stroke. To create a side to side gradient, add a color stop to the gradient bar, then double click on the color to set it to white.
Shown here is a stroke gradient from side to side with the colors going from white to black to white.
Add a color halftone to the line to create the halftone effect. The darker the colors, the larger the dots will be. Where the gradient fades to white it will create smaller dots.