The design of a microphone is primarily driven by its function and desired characteristics, rather than mimicking the shape of the human outer ear. While the outer ear is indeed efficient at collecting sound waves and directing them towards the eardrum, it doesn't necessarily translate into the optimal design for a microphone.
Microphones are designed to accurately capture sound and convert it into an electrical signal. They use various technologies such as condenser, dynamic, ribbon, or electret to achieve this. These designs focus on capturing sound waves effectively while minimizing distortion and noise, and they are often based on principles that differ from the functioning of the human ear.
Additionally, microphones are engineered to be versatile and adaptable to different recording environments and purposes. They need to be sensitive to sounds from various directions, not just directly in front of them like the human ear. Microphone designs take into account factors such as frequency response, polar patterns (directionality), noise handling, and durability, among others.
While there are some microphones that employ specialized shapes or structures to mimic certain aspects of human hearing, such as binaural or stereo recording microphones, these are exceptions rather than the norm. These specialized microphones aim to capture audio with a three-dimensional perspective, emulating the experience of human hearing for applications like immersive audio or virtual reality.
In summary, microphone design is driven by the need for accurate and versatile sound capture, rather than mimicking the shape of the outer ear. Engineers and designers focus on optimizing the microphone's performance, frequency response, and directionality for specific applications, resulting in a variety of microphone designs and technologies.