From invention to commercialisation

Duration of journey depends on whether product is aimed at replacing existing ones or at new markets

I have been struggling with the nagging question about how long it takes for an invention (when an original idea has been articulated) to become commercial (when it is widely sold in market). The grant of a patent is an intermediate step. Based on limited anecdotal evidence, I had averred that it could be 30 to 50 years. Since then readers have offered alternative perspectives on timelines.
 
Joseph Swan obtained the patent for an incandescent bulb as early as 1860, but it took another 23 years for Thomas Edison and Swan to launch electric bulbs under the brand name,