Full Mask Diving

1. The principle and structure of the face mask:

As mentioned above, there must be space in front of the human eye to form a focal point and see things clearly. The function of the face mask is to create a separate space between the human eye and the water, which is the cavity of the face mask, allowing one to see the underwater scenery clearly. The physical principles involved are due to the refraction of light caused by the lens and the cavity, which meets the conditions for human vision. This has also led to the technique of balancing the pressure in the mask cavity.

The importance of cavity pressure balance is second only to ear pressure balance, and the method for balancing the pressure in the mask cavity is quite simple: simply exhale into the mask through your nose. At this point, some may be surprised: how can one breathe through the nose while wearing a mask, especially underwater? This requires a thorough understanding of the mask's construction.

1. The lens is the most critical component of the mask. When purchasing, we select the lens based on our diving needs, as it is a primary factor in deciding whether to buy. The lens is made of tempered glass and is embedded in the frame. The most commonly used type is the single-pane mask, which consists of a single, unbroken piece of glass, offering a wide field of view but cannot be replaced. Double-pane masks are typically two-piece designs, separated like eyeglasses, with one piece for each eye. These lenses can be replaced, but this type of mask does not offer the same wide field of view as a single-pane mask.

Some face masks have a UV coating, meaning that some lenses appear to have a blue, purple, orange, or other colored tint. This coating serves to block UV rays and enhance the richness of the visual field, making colors more vivid. The experience is akin to wearing sunglasses in sunlight.