Filters and Films
Filters show the child aspects of Light her eyes alone cannot see.
Some of them, like thin color transparencies, need a bit of protection to survive in a real classroom so put them in plastic picture frame. Others, like liquid crystal films are pretty tough.
Filters remove light. Films convert energy input into visible light out put.
Most of these presentations can be done with physical equipment. But some, particularly infrared, require the use of a camera or an simple electrical circuit as a sensor.
Some of them, like thin color transparencies, need a bit of protection to survive in a real classroom so put them in plastic picture frame. Others, like liquid crystal films are pretty tough.
Filters remove light. Films convert energy input into visible light out put.
Most of these presentations can be done with physical equipment. But some, particularly infrared, require the use of a camera or an simple electrical circuit as a sensor.
Color Transparencies
These are thin films in clear plastic picture frames to protect them. The easiest thing to do is just look through them but more importantly you can use them to eliminate colors of Light. This is important because the idea must be established that filters do not add light. They take Light away. This filtering of light appears as shades of grey to black depending on the distance on the spectrum from the color of the filter to the color of the light being filtered. So red and blue cancel each other to black.
These are thin films in clear plastic picture frames to protect them. The easiest thing to do is just look through them but more importantly you can use them to eliminate colors of Light. This is important because the idea must be established that filters do not add light. They take Light away. This filtering of light appears as shades of grey to black depending on the distance on the spectrum from the color of the filter to the color of the light being filtered. So red and blue cancel each other to black.
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Polarizing Filters
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Diffraction Grating
Looking through
Looking at
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Double Slit
Use of a double slit filter and a laser is a real dexterity challenge. But once managed the visual effect is dramatic. The difference in appearance between a beam and a split beam is one concrete experience that will underlie the idea of Light as a wave, complimenting the idea of Light as a particle presented with the laser, flat mirror and ping-pong ball.
It is also an experience much more vivid in person than in video.
Use of a double slit filter and a laser is a real dexterity challenge. But once managed the visual effect is dramatic. The difference in appearance between a beam and a split beam is one concrete experience that will underlie the idea of Light as a wave, complimenting the idea of Light as a particle presented with the laser, flat mirror and ping-pong ball.
It is also an experience much more vivid in person than in video.
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Infrared Pass Filter
These were taken with a face side phone camera and a photographic filter blocking all visible light. Most teachers should be able to get a hold of a device which has one camera having no IR filter, usually the selfie side. A simple visible filter can be arranged by combining red and blue filters. The slide show shows an infrared source, a typical TV remote. The camera with no IR filter of its own reveals the light. The IR cut filter stops it. The visible filter stops everything but the IR.
These were taken with a face side phone camera and a photographic filter blocking all visible light. Most teachers should be able to get a hold of a device which has one camera having no IR filter, usually the selfie side. A simple visible filter can be arranged by combining red and blue filters. The slide show shows an infrared source, a typical TV remote. The camera with no IR filter of its own reveals the light. The IR cut filter stops it. The visible filter stops everything but the IR.
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Ultraviolet Cut and Pass Filters
The fact that visually identical disks have completely different effects enables the idea that something invisible is coming from the source. One disk stops it, the other doesn't.
Exposed beads provide a color sorting, labeling exercise.
The fact that visually identical disks have completely different effects enables the idea that something invisible is coming from the source. One disk stops it, the other doesn't.
Exposed beads provide a color sorting, labeling exercise.
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Liquid Crystal Film
Heat is converted to light. |
Magnetic Film
Motion of a magnetic field is converted to light. |
X-ray
Higher on the Spectrum than ultraviolet, as input x-rays produce a light and shadow image.
Higher on the Spectrum than ultraviolet, as input x-rays produce a light and shadow image.
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Shadow
Multiple sources and angles
give control of the light source to the child.
Shadow play is very impressionistic.
Geometric, Experimental, Spontaneous.
The awareness of Light through its absence.
Multiple sources and angles
give control of the light source to the child.
Shadow play is very impressionistic.
Geometric, Experimental, Spontaneous.
The awareness of Light through its absence.
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