The beam angle value sometimes seems to be a bit non-descriptive. Especially due to the influence of the distance between lamp and floor or wall, an estimation is quite difficult. The following formula and the calculator will help you to determine the best fitting beam angle.

The beam angle determines how large the generated light circle appears on the illuminated object. An important factor here is also the distance between the light source and the illuminated object.

GU10 LED illuminants are also available with different beam angles. Here not only the beam angle of the illuminant plays a role. The type of the luminaire or the lamp glass where the GU10 lamp is used is also important.

The beam angle is primarily interesting for directional light sources. These include LED spots or LED spotlights and GU10 illuminates. The beam angle should be chosen according to the location or use-case before purchasing the LED lamp. In the living area there are mainly these three lighting applications:

Basically, large beam angles of 90° or 120° are well suited for illuminating a room over a large area. Small beam angles of 15° to 35° are a good choice for decorative lighting.

The beam angle indicates the angle at which the luminous flux passes out of the LED spotlight. Depending on the distance between the lamp and the floor or the illuminated surface, this creates a light cone with a corresponding diameter.

LED spots are available in different variants, for example for ceiling installation or surface mounting. These are offered with many different beam angles. The angle should be selected according to the application as described above.

A beam angle of 120° is a good choice for the basic lighting of a room. For corridors and pathways within a room, a beam angle of 90° is more recommended.

The calculator helps you to calculate the exact beam angle for your scenario. Here you can calculate the direct relationship between the beam angle, diameter of the light circle and the distance to the illuminated object (floor, table, work surface, wall, picture).

Earlier halogen spotlights usually had a beam angle of 35°. LED spots were first available with similar beam angles in the range of 30°. With integrated prisms or diffuser lenses, modern LED spotlights are now available with beam angles from as little as 10° up to 120°.

The field angle defines the outer area in the light circle where the lamp radiates up to one tenth (10%) of its maximum luminous intensity. Even outside the field angle it is not completely dark, small parts of the luminous intensity are still emitted here as scattered light.

However, if both spotlights have different beam angles, let’s say 15° and 60°, this puts the perceived brightness into perspective. The spotlight with a beam angle of 60° must illuminate a much larger area with the same light output as the 15° spotlight.

Decorative lighting is often used to highlight certain objects in a room. This can be an art object or a picture. Also here the beam angle depends on the diameter of the object and the distance to the light source.

The table gives you an overview of the diameter of the light circle with different beam angles and a ceiling height of 8 feet. For a calculation with your own individual values you can use the online calculator.

科勒照明

A GU10 lamp with a 120° beam angle would probably be screened with a small opening of the lamp glass. The actual beam angle of that lamp would therefore be smaller and part of the brightness gets lost in the lamp glass.

Koehler illumination is obtained by focusing and centering microscopy light on the field of view in order to increase contrast and resolution. Koehler illumination was first introduced in 1893 by August Köhler of the Carl Zeiss corporation as a method of providing optimum specimen illumination. Microscope manufacturers have since designed microscopes with Koehler illumination so the collector lens and other optical components will project an enlarged and focused image of the lamp filament onto the plane of the aperture diaphragm of a properly positioned substage condenser, resulting in higher contrast and resolution images.

The beam angle of LED luminaires and illuminants determines how large the light cone appears in your room. Here you can find out what the bream angle in degrees means and what you should pay attention to when choosing a directional LED light. You will also find a tool to calculate the optimum beam angle for your use case.

For this reason, the illuminated surface appears larger but also much darker. This is why you always have to choose the beam angle in conjunction with the desired brightness on the surface you want to illuminate.

The beam angle of an LED spot determines the diameter of the generated light circle on the illuminated surface or object. The ideal beam angle usually depends very individually on the place of use of the lamp and on your individual use-case. This can be determined very well with the beam angle calculator.

Accent lighting is used to highlight certain areas in a room. This can be a sitting area or a colored wall. Here, the beam angle must be selected individually, depending on the size of the area to be emphasized.

Criticalillumination

Many high quality advanced microscopes that are made with Koehler illumination, if not set up properly, will fail to yield the highest quality images the microscope is capable of. Follow the steps below in order to set up Koehler illumination properly. 1. Place a high contrast slide on the stage, turn on the light and move the 4x or 10x objective lens into position. Set the rheostat control for the light so it is at a comfortable illumination and not overly bright for your eyes. Adjust the condenser height (adjustment knob shown at left) so the top of the condenser is about 0.5cm from the bottom of the microscope slide. 2. Adjust the condenser iris diaphragm (located on the front of the condenser) so it is closed down almost all the way. This will create a dark circle around your image when you look through the eyepieces. Make sure this dark image is centered in the field of view. If the dark circle is off to one side, use the condenser centering screws (Figure 5b below) to center the condenser so the image is directly in the middle of your field of view.

If an LED spotlight is not far away from a wall for example, only a small dotted light circle will be visible. But if you take the spotlight back from the wall, the light circuit becomes larger and larger.

LED luminaires and illuminants have both omnidirectional and directional light sources. Omnidirectional spotlights emit their light evenly distributed in all directions. LED spotlights, on the other hand, are directional light sources. They emit their entire luminous flux in only one specific direction.

With the help of the following trigonometric function (angle function) you can calculate the beam angle yourself with all parameters.

The beam angle has a direct influence on how large the produced light cone appears in the room. You can find the mathematical relationship between beam angle, distance and diameter below:

Besides the beam angle there is also the so-called field angle. In the light circle, the beam angle defines the area where the lamp radiates at least half (50%) of its maximum luminous intensity. The full luminous intensity (100%) is only achieved exactly in the center of the light circle.

There is also a direct correlation between the beam angle and the brightness of an LED lamp. The brightness of LED lamps is given in lumens. If we compare two LED spots with an identical light output of 600 lumens, according to the data sheet they seem to have the same brightness.