The microscopes of the two inventors: Robert Hooke and Anthony van Leeuwenhoek had been imitated and became about equally popular for many years. However, both microscopes too presented difficulties in terms of their microscopes and microscopy usage and offered distinct disadvantages. The compound microscope of Robert Hooke, the double lenses and the long, dark tube caused distortions and lighting problems. On the other hand, the simple microscope of Anthony van Leeuwenhoek, inventor of the microscope was hand held and tiring to use. Finally, sometime around 1830, when glass making and lens grinding were perfected, the compound microscope with its two lenses won out as the definitive model. The microscope with the two lenses was the more efficient one.