The present invention refers to a stencil especially developed for
making drawings and/or other characters, which are viewed so as to obtain a virtual-depth
effect, as well as to a method for using said stencil.
More specifically, the present invention refers to a stencil especially
suitable for making drawings of comic-strip characters, from which a virtual-depth
effect can be obtained.
For a better understanding of the stencil of the present invention,
it is necessary to explain the basic concepts applied to develop it, taken in a
more general plane of human point of view.
The existence of different levels of depth in space is noticed when
the pictures recorded by the two human eyes are gathered together by the brain.
These pictures have a minor difference from one another, which determines the distance
of the objects with respect to the viewpoint.
Similar drawings, disposed in horizontal line and with different
distances from each other, viewed with the focus in the front or behind the paper
give the impression of being on different levels of depth.
If one looks with the focus farther ahead, beyond the surface of
the paper, the greater the distance between the drawings, the closer they will
seem to be. When the focus is placed in front of the paper, the opposite takes
The first procedure described, i.e. focusing beyond the paper, is
also called "parallel" viewing form, since the idea is that we will see the picture
on the left with the left eye and the picture on the right with the right eye (maintaining
the viewing axes of the two eyes nearly parallel to each other), until the brain
can resolve the two pictures as being a single one.
The other procedure, i.e. focusing in front of the paper, consists
in viewing the picture on the right with the left eye and the figure on the left
with the right eye, until the two pictures overlap each other, crossing the viewing
axes of the two eyes.
These two modes of viewing present some variations, which are the
various levels of possible focuses.
It is easier to "cross" the viewing axes ("crossing one's eyes")
than to "open" them. It is easy to look at the tip of one's nose, but difficult
simultaneously to look at two objects which are at a distance greater than the
distance between the eyes, unless one is far away. This causes a parameter to
be established, whereby, so as to facilitate the "parallel" viewing form, the distance
between the pictures should not be greater than the distance between the eyes.
Since the average distance between the eyes and the paper for reading
is of about 25 cm, the ideal is that the distance between the pictures should not
be greater than 45 mm, because, starting from this average to obtain the effect,
it is necessary to move the paper away from the eyes.
Identical drawings arranged side by side with different distances
from one another will produce the impression of being on different planes of depth
when viewed by one of these procedures, while slightly modified drawings can produce
different results. For instance, two triangles are drawn side by side, the one
on the left being equilateral and the one on the right being isosceles, with the
same height. By using the parallel procedure of viewing, the right side of the
virtual triangle (which is formed between the two) seems to be closer than the
left side. By changing the positions, the effect is reversed.
In addition to the above concepts, it is to be noted that the perception
of depth is due to the fact that the pictures recorded by the two eyes are different
but blend together, since each eye occupies a different point in space.
The impression of depth can be simulated in several ways, as for
instance by "cheating" the brains by using two or more drawings arranged side by
There are two basic ways of looking, in order to perceive the effect;
either by focusing beyond the paper, with the viewing axes of the two eyes converging
("parallel" mode), or by focusing in front of the paper, with the view axes diverging
("crossed" mode). These two forms also present variations, which are the various
possible levels of focus. Generically, the effect obtained with one mode is opposite
to that obtained with the other mode. If in the "parallel" mode a picture seems
to be closer, in the "crossed" mode it will seem to be farther away.
Identical pictures arranged side by side can simulate different planes,
depending upon the distance between each other. In the "parallel" mode of viewing,
the smaller the distances, the closer the pictures will seem to be, while in the
"crossed" mode of viewing the opposite takes place.
Similar pictures (with minor differences between each other) side
by side will give the impression of continuous depth, not divided into planes,
if they are either below or above other alignments, which should have some kind
of difference from each other.
According to the present invention, a stencil for making drawings
which present a virtual-depth effect, comprising a base piece provided with letter
elements and/or graphic elements and/or wholly or partially preformed drawing elements,
all of which are cut out therein, the cut-out elements being traceable for reproduction
on a determined surface, the base piece having a plurality of markings indicating
intervals of linear distance, is characterised in that the linear distance between
successive markings increases gradually from one interval to the next.
The present invention also refers to the manner of using such a stencil
to obtain the virtual-depth effect, as will become clear in the following description.
The present invention will now be described in greater detail, by
way of example, with reference to the accompanying drawings, in which:
- Figure 1 schematically illustrates two possible levels of viewing focus, in
- Figures 2a and 2b represent schemes of obtaining the virtual image;
- Figures 3a and 3b represent an example of obtaining different results of the
image from equilateral triangles (right), drawn side by side;
- Figure 4 shows a stencil according to the present invention;
- Figure 5 shows a drawing made with the stencil of figure 4;
- Figure 6 illustrates another stencil produced in accordance with the characteristics
of the present invention; and
- Figure 7 illustrates a drawing made by using the stencil of figure 6.
Figure 1 shows how similar pictures arranged linearly at different
distances from each other can be viewed. Line (a) represents the line of the first
focus, where the pictures "match" sequencially, and line (b) represents the line
of the second focus, where the pictures "match" alternately.
Figures 2a and 2b show the results obtained using the two ways of
viewing the drawings, as described above. Therein we can see the formation of the
virtual image (V.I.) either behind the plane (P), according to the "parallel" mode
of viewing, or in front of the plane (P), according to the "crossed" mode of viewing,
Figures 3a and 3b show the obtention of different results from slightly
modified drawings. Note that in Figure 3a, by the parallel mode of viewing, the
right side of the triangle in virtual image (the third one which appears) seems
to be closer. When viewing from the opposite side, the contrary takes place, that
is to say, the left side seems to be closer.
Figures 4 and 6 show two examples of the stencil for making drawings
to be viewed in accordance with a virtual form, of the present invention, which
constitutes a base piece 1 of any shape and made preferably of plastics or any
other suitable material, with letters 2 and/or graphic elements 3 and/or wholly
or partly preformed drawings 4, all of them cut out therein, which are used for
tracing on a surface such as paper or the like.
In order to enable the combination of drawings which can be seen
as if they were on planes of different depth (virtual image), base piece 1 has
linearly arranged markings (m) at progressively smaller intervals, that is to say,
the first interval between markings (m) is larger than the second interval, which
is larger than the third interval, and so on.
By taking the line of such markings (m) as a base line, it is possible
to repeat the drawings (letters, characters, signs, pictures, etc.) so that they
are aligned with progressively increasing or decreasing distances between them,
which results in an impression of depth when they are viewed with the eyes focused
either in front or behind the surface on which they are drawn. When the focus behind
the drawning surface, the smaller the distance between the pictures, the closer
they will seem to be. When it is in front, the opposite occurs.
According to the pattern adopted in the stencil of the present invention,
smaller intervals result in greater depth between the pictures.
The basic method of using the stencil of the present invention is
- (a) draw a straight line on a sheet of paper to serve as a base for alignment;
- (b) position the stencil for tracing at least one of the cut-out elements of
- (c) traced at least one of the cut-out elements of the stencil onto the paper;
- (d) take note of the position of the stencil along the base line, using one
of the markings (m) on the stencil;
- (e) displace the stencil (and thus the cut-out element being traced) along
the base line until the adjacent marking (m) coincides with the position noted
in step (d);
- (f) trace the cut-out element of step (c) onto the paper; and
- (g) repeat steps (d) to (f) as often as desired. If all possibilities of the
stencil are used, there will then be six drawings the distances between which decrease
from left to right.
When the pictures on the right are viewed with the focus beyond the
surface of the paper, they seem to be closer, and those on the left seem to be
progressively further away. In order to maintain the figures in the same plane,
it is enough to use constant distances between them, repeating the same intervals.
In this case, transfer the drawing, note must be taken of the point, the stencil
should be displaced linearly until the next point coincides with the point noted,
the drawing should transfered to the new position, the first point should be noted
again and the operation may then be repeated as many times as desired. Linearity
of the displacements must always be maintained for new lines which you wish to
In the case of characters, as shown in Figure 6, the stencil may
also have a plurality of indicia (m') on either side of each marking (m) on base
piece 1. This assists the user as a guide when displacing specific areas of the
drawing (letters, characters etc.), for instance the eyes, the nose, the ears,
etc. In this case, the parts of the picture that are desired to be maintained on
regular planes should first be drawn, note of the intervals being taken. Next,
using the smaller indicia (m'), the drawing elements can be displaced progressively,
so as to move them closer or farther away, as desired.
Some examples of drawings with the obtention of a virtual-depth effect,
which have been produced by using the stencil of the present invention, containing
letters, signs, characters and comic-strip characters, are illustrated in Figures
5 and 7.
It should be noted that, in scenes where identical pictures are repeated,
attention should be paid to the distances used. For instance, a picture 15 mm wide
repeated linearly with spacings of 20 mm, when close to another line of drawings
with spacings of 30mm, as illustrated in Figure 8, causes a specific depth effect
which is different from that when close to another line where the spacings are
the double, namely 40 mm, as illustrated in Figure 9. In this case, the two lines
seem to be on the same plane. This difference occurs because the common possible
focus between 20 mm and 30 mm takes place at a determined distance, when the pictures
"match" with those which are immediately beside them, whereas when the distances
are 20 mm and 40 mm, the pictures with distance of 20 mm "match" alternately, that
is to say, at the same point as those of 40 mm, in order to come into focus.