AQUARIUM

AQUARIUM

English Abstract

Abstract
The invention provides an aquarium configured with its front and rear walls
converging toward the top so that at tabletop or countertop height the viewer
can comfortably view the aquarium from an ordinary standing position without
bending over. From this viewing position the viewer cannot see through the
rear face when the aquarium is filled with water, because the viewer's line of
sight is at a sufficient angle that internal reflection occurs.

Claims

WE CLAIM:
1. An aquarium having a transparent body, comprising a bottom and sides
joined to front and rear faces which converge upwardly toward a top opening.
2. The aquarium of claim 1 in which the faces are generally planar.
3. The aquarium of claim 2 in which the front and rear faces are at an acute
angle to the bottom ranging from 60 to 70 degrees.
4. The aquarium of claim 2 in which the front and rear faces are symmetrical
about a vertical longitutinal plane.
5. The aquarium of claim 2 composed of plastic.
6. The Aquarium of claim 5 composed of plexiglass.
7. The aquarium of claim 2 including a canopy having a lamp.
8. The aquarium of claim 1 wherein shallow diverging walls join the front and
rear faces to the bottom.

Description

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Fi~ld of invention
This invention relates to tropical fish ~quariums. In particular, this inventionrelates to an improved aquarium configured to provide better viewing from
an ordinary viewing position.
Background of the Invention ~.
Aquariums are widely used for keeping the numerous varieties of tropical fish ~
which are available today. Typically the aquarium is set up on a table or stand ~ -
at countertop height or lower. Since virtually all aquariums are rectangular, this
makes viewing the fish from the optimum position - perpendicular to an area just -
above the centre of the viewing face - somewhat difficult. Adults usually resortto bendlr~ over, which makes for uncomfortable viewing after a short time.
Furthermore, because the filled aquarium is largely transparent from front to
back, the viewer will see air tubes, electrical cords and other unsightly
distractions behind the aquarium unless a photograph of a marine scene or like
background is affixed outside the rear wall, facing forward, to hide such objects.
The present invention overcomes these disadvantages by providing an
aquarium configured with ns front and rear walls converging toward the top.
Thus, at tabletop or countertop height the viewer can comfortably view the
aquarium from an ordinary standing position, without bending over, even at a
short distance from the aquarium. Either the front face or the rear face may
equally serve as the viewing face. In either case, around the optimum v~ewing
positlon the viewer cannot see through the opposite face when the aquarium is
filled with water, because the viewer's line of sight is at a sufficient angle to the
'rear' face that internal reflection occurs. Thus, around this viewing position the

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viewer sees a reflection on the rear wall of the aquarium.
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Summary of the Invention :
The present invention thus provides an aquarium having a transparent body,
comprising a bottom and sides joined to front and rear faces which converge ~ ~
upwardly toward a top opening. -
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Brief Description Qf the Drawings
In drawings which illustrate by way of example only a preferred embodiment of ~ ~:
the invention, ~ ~ ~
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Figure 1 is a perspective view of the aquarium;
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Figure 2 is a perspective view of the aquarium with canopy;
Figure 3 is a side elevation showing a viewer's line of sight from an ordinary ~ ~ ;
viewing position; and
Figure 4 is a front view of the filled aquarium showing the perspective of the
viewer in Figure 3.
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Detailed Description of the Invention
As illustrated in Figure 1, the aquarium 10 is formed with large generally planar
faces 20,22 inclined relative to the bottom 24. In the embodiment shown, a
single sheet of suitably thick p!exiglass is bent to form the faces 20,22, the
bottom 24 and the shallow diverging walls 26,28 and is then bonded to the
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ends 30,32 in a conventional fashion, leaving an opening 12 at the top for
access to the aquarium interior. Plexiglass is preferred for its transparency,
ease of manufacture and strong bonding properties, but any suitable plastic or
glass may be used.
In a preferred embodiment a top to cover the opening 12 comprises a plastic
canopy 14 containing a conventional aquarium lamp switched at 16, an
opening or notch (not shown) for air tubes, heater cords and the like, and
optbnally a covered feeding hatch 18.
The large faces of the aquarium 20,22 are angled acutely from the bonom 26,
preferabq in the ran~e of 60 to 70 degrees. Preferably also the faces 20,22 are
symmetrical about the vertical longitudinal plane P through the centre of the ~ i;
body 12 (shown in Figure 3), so that either of the faces 20,22 can serve equallyas a viewing face, and the aquarium is thus well suited to be placed in the
centre of a room. It is not necessary to include the diverging walls 26,28, which
are provided for aesthetic purposes oniy. The diverging walls 26,28 should be
shallow enough that the gravel will cover them, or else a viewer in an ordinary
viewing position will readily see through them.
Provided that the large faces 20,22 converge toward the top, so that the
aquarium is essentially a triangle in cross-section as seen in Figure 3, the
aquarium 10 becomes a prism when filled with water, and the viewing faces
20,22 refract light according to well known principles of optics. A particularlyinteresting effect results when the lamp is on because to the viewer the light is
effectively originating inside the prism.

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Figure 3 shows the face 20 as the viewing face, for purposes of illustration. ~ ;~
When the aquarium is filled with water, the rear face 22 becomes more
reflective as the viewer's line of sight approaches the critical angle. Because of
the angle of the viewing face 20, the ideal viewing position is as shown in
Figure 3, perpendicular to an area just above the centre of the viewing face 20. -
This is an ordinary standing position for adults if the aquarium is at tabletop or
countertop level. At this position, and within a range around it, the viewer's line
of sight is close to or past the critical angle, at which point the rear face 22 is
completely reflective. This is shown notionally in Figure 3, and Figure 4 shows
the image seen by the viewer in Figure 3.
The invention ha~ing thus been described by reference to a preferred
embodiment thereof, it will be obvious to those skilled in the art that variations
and modifications of the invention may be made without departing from the ~ ~ i
scope of invention, as set out in the appended claims.
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Representative Drawing