Light

Concave lens

A lens with a center thinner than its edges. Concave lens. A concave lens spreads out light rays, making objects look smaller.

Concave mirror

A mirror with a surface that curves inward. Concave mirror. A concave mirror focuses light to a point and can make images appear larger when viewed up close.

Cone cells

The retina cells that work in bright light, and help us see color. Cone cells. Cone cells are specialized cells in the eye that allow us to see colors and fine details in well-lit conditions.

Convex lens

A lens with a center thicker than its edges. Convex lens. A convex lens bends light inward to a focal point, magnifying objects.

Convex mirror

A mirror with a surface that curves outward. Convex mirror. A convex mirror is a type of mirror that bulges outwards, making objects appear smaller and providing a wider field of view.

Diffuse reflection

Reflection of light at many angles by a rough surface. Diffuse reflection. It occurs when light hits a rough surface and scatters in many directions, making objects visible from various angles.

Energy absorption

The transfer of energy from a wave to an object, like sound energy when it hits a wall. Energy absorption. Energy absorption is when an object takes in energy from waves, like sound or light, instead of reflecting it.

Fluorescent light

Visible light produced when phosphor is hit by ultraviolet light. Fluorescent light. Fluorescent light is created by using ultraviolet light to excite a coating inside a bulb, which then emits visible light.

Focal point

The point at which light rays converge after passing through a lens is called the focal point. In simple terms, the focal point is where light meets after being bent by a lens to create a clear image.

Hologram

A three-dimensional photograph created using lasers. Hologram. A hologram is a picture that appears in 3D and is made with laser light.

Incandescent light

Light produced when a metal is heated until it glows, it was used in old light bulbs. Incandescent light is light that comes from heating a material until it glows.

Laser

A device that produces a narrow light beam of a single color and frequency. Laser. A laser is a tool that emits a concentrated beam of light, all in one color, used in things like cutting materials or medical surgeries.

Law of reflection

States that the angle of incidence is equal to the angle of reflection. Law of reflection. In simple terms, the law of reflection means that when light hits a surface, it bounces back at the same angle it arrived.

Lens

A transparent object with at least one curved surface, light bends when passing through it. A lens is a tool that focuses or disperses light rays.

Light

Electromagnetic energy that travels in waves, not all light is in the visible spectrum. Light. Light is a form of energy that moves in waves and makes things visible to our eyes when it's within a certain range called the visible spectrum.

Microscope

An instrument that uses lenses to magnify small objects. Microscope. A microscope is a tool that helps you see tiny things that are too small for your eyes to see alone.

Mirage

The image of a distant object created when refracted light passes through air layers of different densities. Mirage. A mirage is an optical illusion where light bends in the air, making objects appear displaced or distorted.

Opaque

A material that does not let any light pass through. Opaque. In simple terms, opaque objects block light completely, so you can't see through them.

Pigment

A colored chemical compound that absorbs some colors of light and reflects others. Pigment. Pigment is what gives color to materials by absorbing and reflecting different wavelengths of light.

Plane mirror

A flat mirror that produces upright images of objects. Plane mirror. A plane mirror is a smooth, flat surface that reflects light evenly, creating a clear image right-side up.

Pupil

The opening at the center of the iris, through which light enters the eye. Pupil. The pupil is the part of the eye that adjusts its size to control how much light enters, helping us see better in different lighting conditions.

Reflecting telescope

A telescope that uses concave mirrors to reflect and focus light from distant objects. Reflecting telescope. A reflecting telescope is an instrument that uses mirrors to gather and focus light from stars and other celestial bodies.

Refracting telescope

A telescope that uses convex lenses to focus light from distant objects. Refracting telescope. A refracting telescope is a device that uses lenses to gather and focus light from faraway objects to make them appear closer and clearer.

Regular reflection

The reflection that occurs when parallel light rays hit a smooth surface and every ray is reflected at the same angle regular reflection. Regular reflection is when light bounces off a smooth surface in a uniform direction, like a mirror.

Retina

The light-sensitive layer at the back of the eye, it contains rods and cones. Retina. The retina is the part of the eye that detects light and helps send visual information to the brain.

Rod

A receptor cell in the retina that works in dim light, but cannot detect color. Rods are cells in the eye that help us see in low light conditions, but they don't perceive color.

Total internal reflection

Occurs when light hits the boundary between two materials but is reflected back. Total internal reflection. It is when light completely reflects inside a material instead of passing through, like light bouncing back into water from its surface.

Translucent

Allows some light to pass through but scatters it. Translucent. Translucent materials let light in but blur it, so you can't see clear images through them.

Transmission

The passage of light through a material. Transmission. Transmission is when light or other forms of energy pass through a material without being absorbed.

Transparent

Allows light to pass through. Transparent. In science, transparent means something that you can see through because it lets light go through it.