Depth Finder
A depth finder is a kind of device that is used to assess water depth. These devices are most commonly used to work out the depth of an area or piece of water and have a variety of commercial uses. Depth finders can range in complexity from the very simple to the extremely complicated. The kind of devices that are used in any application of this sort may depend on why they are being used and by whom.
So, for example, if you wanted to assess how deep a part of a pond or river was then you could use a simple depth finder such as a sounding line. These depth finders can be as basic as a piece of rope with a weight on the end. Dropped into the water (remembering to hang on to one end of course!) the weight will sink to the bottom. The depth can then be measured by measuring how much of the rope is wet.
Many depth finder devices are a little more complicated than this, however. These devices are often used by navies and by commercial shipping concerns. If you have a large ship that needs to navigate an expanse of water it is, after all, important to know whether the water will be deep enough for the ship to pass through and whether there are any obstacles in the way that might make it difficult for the ship to do so.
Nowadays sonar is often used as a depth finder. This allows a user to assess the depth and layout of an area of water by using sonar technology. Sound is used here to put together a picture of what is going on underwater. Although this kind of technology is fairly complex it works on simple principles. Sound will travel until it hits an object at which point it will be reflected back and can be used to produce accurate measurements.
Fishermen and commercial fishing companies can also use a type of depth finder known as a fathometer or fish finder. This works in a similar kind of way to sonar and is more commonly used to work out where shoals of fish are situated by using echo sounding systems. Again, the sound will hit the fish and bounce back, showing where they are located. Echo sounding that uses sound waves and their echoes to measure distance underwater may also be used to assess the depth of water.