You are right! Shape in figure (a) is tapered at the top (known as Oval shape) and the other one is broader at the top (known as Isometric or Square shape). Now, why is this an important factor?
An Isometric racket has 30% bigger ‘sweet spot’, which means, more area to hit the shuttle right (without banging on the string ends or the frame). To gauge the importance of hitting the shuttle with the sweet spot, it is enough to say that it is one of the 5 first-principles of badminton.
Wow! everyone then should buy an Isometric racket, right?
Not really. It depends on the level of your game. Challengers/Champs/Pros have the ability to use the sweet spot consistently even if the area is smaller (because of their high accuracy). What they require is more power in their shots. Oval shape rackets serve this need by offering lesser ‘sweet spot’ area but delivering much more power in the shots.
Hence, if you are a Newbie/Rookie/Middler, you should go for an Isometric racket but if you are a Challenger/Champ/Pro then you should go for an Oval shaped racket.
Is it that simple? Well, yes. No point in bringing more complications here.
However, just for the record, some Challengers/Champs/Pros also use Isometric when they are playing Doubles as the broader ‘sweet spot’ helps in hitting the shuttle travelling at higher speeds (unique to Doubles).
Options in the market:
- Isometric: Yonex, Victor
- Oval: Yonex, Victor