What invisible flicker do different types of light bulbs have?

Old fashioned (or very cheap) fluorescent bulbs flicker at twice the mains frequency if they use magnetic ballasts driven directly from the AC. Modern fluorescent bulbs use an electric ballast that runs at 5khz - 40khz (for CFLS), then the electrons stay excited for longer than the switching frequency and the light output is constant.

LEDs are constant, unless you count the individual electrons moving over the diode junction! High power LEDs normally have their own driver chip which carefully controls the current and voltage of the diode so they are less sensitive to the supply power.

Solid state lasers are essentially the same as LEDs.

edit: some very cheap LED lights, eg christmas decoration are driven directly from AC - using the diodes themselves to rectify it - these will flicker at the 1/2 mains frequency.

LEDs are often driven so that they flicker at whatever frequency the driver designer chose. Some types of LEDs are prone to burning out when driven with a constant current and it is possible to get a higher average brightness by turning them on for short pulses. LED dimming is also achieved by pulse width modulation, rather than changing the peak current.

Incandescent lamps have a lot of thermal inertia. Because they are hot metal, the filament can't heat up and cool down 120 times per second, so they don't flicker.

Flourescent lamps work by a glowing gas (Mercury) that gets phosphor glowing on the inside of the tube. White phosphor is pretty fast, so a cheap flourescent can flicker. Radar and sonar displays used to use a very slow green phosphor that would not flicker, but who wants a green light bulb?

LEDs are super fast. If you drive them with DC, they will not flicker. But, LEDs use very low voltage (around 1 volt) and converting 12 or 120 volts to a small DC using resistors or transistor in old-fashioned "linear" regulation wastes most of the power. So, folks usually pulse width modulate (PWM) LEDs. This turns them on and off at a very fast rate. It wastes very little power and allows you to vary the brightness by changing the % of the time it is on. If the on/off frequency is high enough, you can't see any flicker. One issue is that if you move your head quickly, the LED will look like a dotted line. Modern car tail lights have this problem.