Introduction: Opposcope for Transparent Footprints : How to Look at the Sky and the Ground at the Same Time

By

Opposcope is an optical device that allows you to see both the sky and the earth at the same time.

How it works: The images captured by the two magnifying lenses (one facing upwards and the other facing down) are reflected by two 45-degree mirrors and projected onto the translucent plastic sheet. It works just like the viewfinder in a twin-lens reflex camera. Due to the soft focus of the rear projection, the image has dreamlike quality.

Warning: When you walk around with Opposcope, watch your steps. Do not use the Opposcope where there is traffic. Do not attempt ride bicycle, horse, skate, ski, surf or drive a vehicle or operate power tools and machineries while viewing Opposcope. While the translucent plastic sheet will soften the intensity of the light, staring at the sun with Opposcope may harm your vision. Never look at the sun through Opposcope without the translucent plastic sheet installed.

Step 1: Tools and Materials

Tools:

# Computer and printer

# Utility knife,

# Straight edge,

# Scissors

# Circle cutter (optional)

# Cutting mat

# Ballpoint pen with empty ink : to score the card stock paper to make clean fold

# Paper glue (or Scotch tape)

# Pencil

# Aluminum foil adhesive tape (or any adhesive tape will be OK)

Material:

# 8.5” x 11” Card stock printer paper : 3 sheets

# 1” Magnifying boxes (3x magnification) : 2

# Plastic mirrors ( 2” x 2 ⅛”, thickness: ⅛” or 3mm) : 2. You can find this at plastic stores. Sometimes they sell cheep odd sized ones.

# Translucent plastic sheet (85mm x 50mm x aprox 0.5mm thick) : 1, I used a shitajiki writing board found at a Daiso Japanese dollar store.

Step 2: Prepare the Mirror and the Screen

Cut the plastic mirror in the size with a band saw. Sand down the burrs.

You will need two mirrors for one opposcope.

Cut the translucent plastic sheet in size. You will need one for each opposcope.

Step 3: Prepare the Paper Parts

Download the three PDF files and print them out in 100% scale on 8.5”x 11” card stock papers.

# opposcope_1_wedge.pdf

# opposcope_2_box.pdf

# opposcope_3_viser.pdf

Three paper parts will become:

Mirror wedge

Projection screen/mirror box

Visor

Score all the dotted lines with the ball point pen (with runout ink) using the straight edge on the cutting mat. This process is important to make crisp folds so that all the parts will fit nicely.

Cut the 6 circles using the circle cutter. Practice cutting with scrap paper before you actually cut your piece. You may use a utility knife but the result will not be as clean as when you use a circle cutter.

Cut all the solid lines using the scissors or utility knife. Fold all the dotted lines. They are all “valley” folds.

Attachments

Step 4: Assemble the Box

The mirror wedge:

opposcope_1_wedge.pdf

Fold all the dotted lines. After folding the last tab it should hold itself. No glue or tape is necessary.

Making the Screen/mirror box: opposcope_2_box.pdf

Fold it into a box and place the mirror wedge inside of the box. Place the two mirrors on the wedge. Place the plastic sheet over the mirrors. Fold the lid and close the box. The box should hold all the parts without glue or tape.

Step 5: Make the Visor

Cut opposcope_3_viser.pdf in half and fold at the dotted lines.

Place the box inside of the visor. The holes on the box and the visor should line up. Draw the seam line with pencil. Glue (or tape) two visor pieces together at the seam line to make a rectangular tube. Make sure the box will slide inside of the visor.

Attach the lenses on the holes on the visor with aluminum tape. It can be any tape if you prefer.

Step 6: Assemble

Slide the box inside of the visor with the screen facing inside. If you put the box on the edge of the visor, the holes on the box should line up with the lenses on the visor.

Now you are done!

Step 7: Try Walking Around!

Hold the Opposcope vertically in front of your face and walk around. Make sure your hands are not blocking the view over the lenses.

Opposcpe needs lots of light to be visible. You’ll have the best experience outside during daytime or in a well lit room. Watch your steps and be careful with traffic outside.

Step 8: Upgrading

Black Version

For better results you may want to use black colored paper for visor and the other parts. This will help to make the projected image appear clearer. The only problem is the printer ink will not show on black paper. You can use the Opposcope you just made as a pattern and trace it over the black paper to make another Opposcope version black.visor