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Mosquito eyes

 Mosquitoes, like many other insects, have compound eyes. Compound eyes are made up of numerous individual photoreceptor units called ommatidia. Each ommatidium consists of a lens, a cornea, a crystalline cone, and a light-sensitive receptor cell.  Mosquito compound eyes are typically large in proportion to their body size and are positioned on the sides of their head. They have a spherical shape and provide mosquitoes with a wide field of vision, allowing them to detect movement in different directions.  The compound eyes of mosquitoes are designed primarily for detecting changes in light intensity and movement rather than forming detailed images. Each ommatidium captures a small part of the overall image, and the mosquito's brain processes the input from multiple ommatidia to form a composite picture of its surroundings. Mosquitoes are attracted to certain stimuli such as heat, carbon dioxide, and chemicals in human sweat, which help them locate potential hosts for blood meals. T
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Contact lens parameters

 Contact lenses are medical devices that are worn directly on the cornea of the eye to correct vision or for cosmetic purposes. There are various parameters associated with contact lenses that are important for fitting and prescribing the right lenses for individuals. Here are some common parameters: 1. Power (Refraction): Contact lenses are available in different powers to correct nearsightedness (myopia), farsightedness (hyperopia), astigmatism, and presbyopia. The power is measured in diopters (D) and can be positive (+) or negative (-) depending on the type of vision correction needed. 2. Base Curve (BC): The base curve determines the curvature of the contact lens. It is typically measured in millimeters (mm) and represents the curvature of the inner surface of the lens. The base curve is chosen to match the curvature of the cornea for proper fit and comfort. 3. Diameter (DIA): The diameter of a contact lens is the measurement across the lens from edge to edge. It is usually measur
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Base Curve of contact Lens

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The base curve of a contact lens refers to the curvature of the back surface of the lens. It is measured in millimeters and is one of the main characteristics of a contact lens. The base curve is important because it determines how well the lens will fit on the eye. A lens with a base curve that is too flat may not conform to the shape of the eye and may cause discomfort or irritation. On the other hand, a lens with a base curve that is too steep may be difficult to insert and remove and may cause lens dislocation or other problems. To find the right base curve for a contact lens, an optometrist will measure the curvature of the eye using a tool called a keratometer. This instrument measures the curvature of the front surface of the eye (the cornea) and helps the optometrist determine the appropriate base curve for the lens. In addition to the base curve, other factors that can affect the fit and comfort of a contact lens include the diameter of the lens and the material o
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