Home Ophthalmology What is the name of the volumetric figure of the oval. Classification and identification of elliptical oval curves

Ophthalmology

What is the name of the volumetric figure of the oval. Classification and identification of elliptical oval curves

- (from lat. ovum egg) 1) oblong round. 2) a curved line shaped like an egg. Dictionary of foreign words included in the Russian language. Chudinov A.N., 1910. OVAL is a closed oblong round line. Dictionary of foreign words included in ... ... Dictionary of foreign words of the Russian language

A, m. ovale m., German. Oval, it. ovato lat. ovatus, ovalis ovoid. Oblong circle, egg-shaped thing. Exchange. 159. Oblong circle. Dal. Outline in the form of an elongated circle, in the shape of an egg. BAS 1. The figure is round or oval without ... ... Historical Dictionary of Gallicisms of the Russian Language

Dahl's Explanatory Dictionary

Husband. oblong circle; a true oval forms an ellipse, a long circle. Oval, long-round, longish round, long-faced. ness of wives. oblong roundness. Oval lathe chuck, running on two ostia, centers, eccentric, for ... Dahl's Explanatory Dictionary

Cm … Synonym dictionary

- (from lat. ovum egg) a convex closed flat curve without corner points, for example. ellipse... Big Encyclopedic Dictionary

Oval, the son of Joktan (Gen. 10:28), the ancestor of a certain Arab. nationality; see Ebal (2) ... Brockhaus Bible Encyclopedia

OVAL, oval, husband. (French oval from Latin ovum egg). ovoid shape; a figure bounded by a curved line of an ovoid shape. Explanatory Dictionary of Ushakov. D.N. Ushakov. 1935 1940 ... Explanatory Dictionary of Ushakov

Suffix A word-building unit that stands out in an adjective with the meaning of an age feature called the noun from which the corresponding adjective is formed (year-old). Explanatory Dictionary of Efremova. T.… … Modern explanatory dictionary of the Russian language Efremova

OVAL, a, husband. Closed ovoid outline of something. Handsome about. faces. Explanatory dictionary of Ozhegov. S.I. Ozhegov, N.Yu. Shvedova. 1949 1992 ... Explanatory dictionary of Ozhegov

- (Oval, Bowl) The closed form of some signs or their parts, forming a circle or an ellipse. The slope of the axes of the ovals [the axis of symmetry of the oval letters] is an important typeface feature [type characteristics], which characterizes the shape of the font ... ... Font terminology

Books

, Alena Rossoshinskaya. The face is a mirror not only of the soul, but also of well-being. Each of us at our age dreams of being cheerful, healthy and attractive. Straight back, noble head position, taut oval…
, Lykova I.A. Children aged 5-10 love to draw themselves and love to watch how adults draw. And our book invites them to watch how the artist draws. And go with him the way from ...

oval- a, m. ovale m., German. Oval, it. ovato lat. ovatus, ovalis ovoid. Oblong circle, egg-shaped thing. Exchange. 159. Oblong circle. Dal. Outline in the form of an elongated circle, in the shape of an egg. BAS 1. The figure is round or oval without ... ... Historical Dictionary of Gallicisms of the Russian Language

Dahl's Explanatory Dictionary

Cm … Synonym dictionary

- (from lat. ovum egg) a convex closed flat curve without corner points, for example. ellipse... Big Encyclopedic Dictionary

Oval, the son of Joktan (Gen. 10:28), the ancestor of a certain Arab. nationality; see Ebal (2) ... Brockhaus Bible Encyclopedia

OVAL, a, husband. Closed ovoid outline of something. Handsome about. faces. Explanatory dictionary of Ozhegov. S.I. Ozhegov, N.Yu. Shvedova. 1949 1992 ... Explanatory dictionary of Ozhegov

oval- (Oval, Bowl) The closed form of some signs or their parts, forming a circle or an ellipse. The slope of the axes of the ovals [the axis of symmetry of the oval letters] is an important typeface feature [type characteristics], which characterizes the shape of the font ... ... Font terminology

Books

How to get rid of the second chin and restore the oval of the face, Alena Rossoshinskaya. The face is a mirror not only of the soul, but also of well-being. Each of us at our age dreams of being cheerful, healthy and attractive. Straight back, noble head position, taut oval…
Toys and animals. Painting with mom. 5-8 years old, Lykova I.A. Children 5-10 years old love to draw themselves and love to watch how adults draw. And our book invites them to watch how the artist draws. And go with him the way from ...

OVAL Dahl's Explanatory Dictionary

OVAL- husband. oblong circle; a true oval forms an ellipse, a long circle. Oval, long-round, longish round, long-faced. ness of wives. oblong roundness. Oval lathe chuck, running on two ostia, centers, eccentric, for ... Dahl's Explanatory Dictionary

oval- Cm … Synonym dictionary

OVAL- (from lat. ovum egg) a convex closed flat curve without corner points, for example. ellipse... Big Encyclopedic Dictionary

Oval- Oval, the son of Joktan (Gen 10:28), the ancestor of a certain Arab. nationality; see Ebal (2) ... Brockhaus Bible Encyclopedia

OVAL- OVAL, oval, husband. (French oval from Latin ovum egg). ovoid shape; a figure bounded by a curved line of an ovoid shape. Explanatory Dictionary of Ushakov. D.N. Ushakov. 1935 1940 ... Explanatory Dictionary of Ushakov

-oval-(th)- suffix A word-building unit that stands out in an adjective with the meaning of an age characteristic called the noun, from which the corresponding adjective is formed (one-year-old). Explanatory Dictionary of Efremova. T.… … Modern explanatory dictionary of the Russian language Efremova

OVAL- OVAL, husband. Closed ovoid outline of something. Handsome about. faces. Explanatory dictionary of Ozhegov. S.I. Ozhegov, N.Yu. Shvedova. 1949 1992 ... Explanatory dictionary of Ozhegov

Books

How to get rid of the second chin and restore the oval of the face, Alena Rossoshinskaya. The face is a mirror not only of the soul, but also of well-being. Each of us at our age dreams of being cheerful, healthy and attractive. Straight back, noble fit of the head, taut oval ... Buy for 228 rubles
Toys and animals. Painting with mom. 5-8 years old, Lykova I.A. Children 5-10 years old love to draw themselves and love to watch how adults draw. And our book invites them to watch how the artist draws. And go with him the way from ...

The Exposed Logo, or Psychogeometry Taranenko Vladimir Ivanovich

4.3. Oval: dynamics of a bipolar figure

We still don't know what's inside our globe. For some reason, it will be flattened from the poles. It seems to be no longer a ball. A geoid, approximately a triaxial ellipsoid, a spheroid.

Interpretation of information from: Soviet Encyclopedic Dictionary. - 4th ed. - M, 1990. - S. 464

In a circle, all radii and directions are equal. But in the oval, as in socialism, everyone is equal, but someone is still longer!

Kozma Prutkov. social geometry

If the circle stretched out, then he went to the service. What self-sufficiency is there!

Kozma Prutkov, collegiate assessor

It is somehow slightly dangerous to be psychologically ambivalent. Suddenly you pull yourself apart in different directions.

Meditation at the crossroads

An ellipse is a flat closed oval curve, for simplicity we will say an oval. Well, if we compress the ball (note this moment!), Then we get a three-dimensional curvilinear closed body ellipsoid. Phenomenally (that is, it is revealed, as we have already said) - neither an oval nor an ellipsoid is no longer a circle and not a ball, respectively. The oval and ellipsoid have an axial direction and two poles, that is, the figures represent a bipolar figure. But the center is not expressed! Of course, it is there, but unlike a circle, you can’t easily poke into it. You have to search and aim. Again, an oval, unlike a circle, has a much larger area of contact with the medium in the “lying” position (cf. Fig. 4.1 and 4.4). But what unites them both is the property of roundness. Still related figures.

At least they do not conflict with the environment. But if the circle shrinks inward, then the oval tends to move and change. In this aspect, it is very reminiscent of a rectangle. The one moves away from the static rationality of the square, and the oval away from the involving depth of the circle. Where, perhaps, the only way out is through irrational perception. But the oval no longer has such a mission. Its center is much less pronounced and, we dare to say that it is weakened. In any case, the poles or extremities of the oval appear stronger. Note that in the oval it is not difficult for you to see two divergent circles (Fig. 4.5). Each with its own local center. But the most important center in the oval is already under the question mark. Why is that?

Option one. Initially, two conflicting trends or missions were laid down. Perhaps two leaders who had diametrical ideologies. So they "stretched" the circle in different directions. Although, in general, they agreed on a single concept. Moreover, in a charismatic style - from the center of the circle. In practice, however, there is a diversity of ideologies and strategies. Although the unity, oddly enough, is still preserved. The oval is a completely holistic and harmonious figure. Absolutely not causing any destructive contradictions. A kind of dialectical unity, continuity and harmony of opposites. Well, so be it, in the form of an oval.

Option two. The circle under the pressure of the medium is forced to transform into an oval, and the ball into an ellipsoid. So to speak, partly forced, but already irreversible evolution of a strictly centric figure (Fig. 4.6). This wonderful idea was suggested to the author by his long-term comrade and colleague Yaroslav Korenevsky. Thank you. If the circle is squeezed, it will stretch into an oval. And then he will have dynamics. Care, search, development.

But the movement in depth is definitely suspended. The oval has become more practical than the circle. In any case, it moves in the environment, trying as much as possible not to disturb it. The oval solves its problems with minimal environmental disturbance. For which we are grateful to him.

The third option is simply the evolution of a circle into an oval. At least by virtue of the requirements of internal metaphysics. For some reason, you need to go out on the road, and not engage in meditation and self-deepening. The process of retraction is replaced by a search for alternatives. And, mind you, again without internal tension and drama. In family divorces, this is called: "let's live apart, but at the same time together, most importantly - without scandals." Look, the family will survive. It's the same in business affairs.

Take a closer look at the configuration of the endings of the oval, that is, its poles. In other words, look how pointed or rounded, blunted the oval is. The sharper the ends of the oval, the more actively and sharply it cuts the environment in its movement (Fig. 4.7). The structure is more combative in the axial direction than adaptive. And at the same time, the medium is gently cut, so there are no shocks and force pressure. This is how the Titanic died at one time, colliding with an iceberg. It would be better to go to the ram. The pointed oval has only side contours - a weak point. Therefore, he can rip up the abyss surrounding him only frontally. But with a striking effect, without noise and imperceptibly. The tip is sharpened and rounded.

The rounded oval (Fig. 4.8) is much calmer in this regard. It really moves in such a way as to minimize external resistance. He does not need an attack, but, perhaps, the preservation of his integrity. And, of course, the achievement of some new mission, due to which the oval was transformed from a circle.

In logos, pay special attention to how the oval itself is located in the spatial plane. Standing vertically “on the priest” is very risky unstable and expresses, perhaps, megalomania, coupled with ideology. So I want to carry my ideology into the sky. The oval lying in a horizontal plane has unequivocally moved into the area of grounded practicality. The flight of the idea temporarily, and perhaps by calculation, stopped. Or it was originally supposed to be implemented on a practical, and sometimes even utilitarian level. In other words, first of all, the result, even if small. The lying oval does not want to take risks. The reasons for this are not difficult to guess just by looking at the real logo. The oval, located obliquely, at an angle, is trying to achieve progressive success through active movement and the development of its own ideas. This is if the angle of inclination is directed to the right. The slope of the oval to the left is a return to the past, an attempt to return to the roots and realize unfinished ideas, maybe nostalgia.

But with a rectangle, things look more fun. The answer is clear. Both have an axis and move along their axis. The main thing is that they match. The oval should be extended in proportion to the rectangle. We also take into account that the rectangle as such does not have a center, but it is more pronounced near the oval. This means that the integrity and inner meaning of the movement are preserved. There is a typical symbiosis here (Fig. 4.10).

In the same way, the oval will not tolerate any other figure within itself. His center is already “spreading” in opposite directions, and here inside there is some other element with its own program. Then certainly the poles of the oval with adjacent margins will give a tear from the center, which is no longer the center. Someone else is there (Fig. 4.11).

COLOR and OVAL. There are colors that enhance the centrifugal tendencies of the oval, and there are, on the contrary, those that hold it together and hold it together. Again, a certain color can enhance the dynamics of the oval, or you can drown it out. Similarly, there is the possibility of either strengthening or weakening the center. So the oval interacts very selectively with color. So.

White the oval is kind of nonsense. The center is noticeably weakened, or rather, completely dissolved in white. The axial direction is also not expressed. There is a general dynamics, but some completely undefined. White is looking for, does not know what. And then, he has no ideology, and the oval just has its own idea. But it cannot manifest itself through the color white. So, there is a search for something new ahead. Maybe this is the beauty of the white oval? Note that the search for a new one takes place without a war with the environment, and there are no destructions inside. The white oval wants something and strives somewhere, but does it organically and, perhaps, with hope.

At black oval is different. It totally draws in itself, while the dynamics of movement is slowed down, although not inhibited. The axis of symmetry is weakened. The black oval moves outside of logical being. Therefore, the internal ideological center has an attractive and gathering power. The black oval is harmonious, but it is all inside, in itself. And somewhere in the depths directed. Contacts with the external environment are rigidly outlined. A kind of retracting polynya. However, due to the movement of the oval, a sense of doom does not arise.

Grey the oval is absolutely tolerant in its centripetal directions. The same applies to the external environment. The axial symmetry and the center are blurred, but in general everything is in harmony. Soft calm movement without internal contradictions. The multidirectionality of the poles is smoothed out by a certain balanced dialectic. Such an oval is seeking and contemplating. Yes, the ideological component is also completely non-intrusive. The gray oval has no projections to live at the expense of others and attribute their problems to the external environment. He is comfortable, balanced, tolerant and seeks his own way without harming others.

Scarlet and red ovals are very active in their expansion. Such ovals attack the environment in the name of their ideology. Their poles represent the impact force. The center is also like an explosion. The oval is actually quite an adaptive and cautious figure, but in this color it becomes unsafe. Take note just in case. Add here the internal tension between the figure and the scarlet or red color, which are completely uncharacteristic in nature. Destructive processes inside the oval will only intensify. I wonder how long it will last in this state?

Purple and crimson have already been softened. Adaptability increases, internal integrity is preserved. These are good ovals. Collective and going to their mission. They will be able to solve their problems productively.

Blue the oval is very organic. He is amazingly cumulative. A blue (especially dark blue) oval has no opposition between the poles and the center. Everything is one and the same. Again, such an oval is more directed into the depths of its essence than outward. His movement and development is deeply motivated. It grows from within. And no absolutely external aggression. Soft advancement and unified tension-free integrity.

Dark violet the oval is very deeply mystical. Or rather, he is a synthetic. Can connect the incompatible and reveal the truth. The purple oval has no external obstructions. He dives much deeper. And achieves more. Without any aggressive expansion. But what is generated by the purple oval can sometimes be invaluable.

FROM green oval somehow everything is uncomfortable, and most likely even bad. Although in the sublunar world there is nothing absolutely good and absolutely bad. Everything has its own use, its own measure and its own mission. The green color is extremely static and rational, while the oval is dynamic and irrational in nature. Some kind of mismatched pair. Symbiosis and complementarity does not occur here. The green color clearly inhibits the activity of the oval, trying to structure and rationalize it. The center of the figure, its poles, the leading axis - everything is totally remade into a single mass in green. All that remains is the rigid outer contour. And also the program is totally green in spite of the inner essence of the oval. Someone suppressed someone. It happens that way too. But. a dark green oval, and even better - a little bluish, will still balance the oval's bipolarity. A certain gathering stability appears, and the movement occurs inward, and not in breadth. Which is not bad.

Yellow the oval cheerfully radiates energy. Contradictions are erased, the center and outer contours are blurred in the yellow glow, but the main thing remains - movement and development, the search for something new. Yellow de-emphasizes the centerline, but offers many other options. There is no depth, but external expansion is actively asserting itself. Exclusively in a positive and cheerful perspective.

Brown and even better golden brown the oval is both comfortable and prestigious (if it is golden). With a gentle movement and his ideology, he will certainly achieve prosperity. Deep ideas will not worry him much, but coziness and comfort will take first place among his needs.

PEOPLE-OVALS. They are ideological, but contradictory in their deep essence. It is clear why. Going and developing simultaneously in diametrically opposite directions is not free for the psyche and mentality. From this, frustrations (tensions) and neuroses can sometimes arise. Although, to the credit of oval people, it can be said that they maintain their inner integrity and spiritual harmony as much as possible. Despite the turmoil and attraction of the soul. Contact, but to the end are revealed to very few and far from immediately. They are not aggressive and in no way blame the world for their problems. Well adapted to the environment. Movement and development occur in a soft form. As a rule, such people do not cause antipathy in the team and among relatives. It is easy to communicate with them, if you do not touch on the purely internal problems of this person. Although here the key to the soul is hidden. Oval people really need a person who understands them nearby. They are also happy to have companions. They are drawn to their own kind, for who does not understand the oval better than the same oval? They can make a good career in management. Leaders from ovals turn out to be soft, tolerant, but by no means weak-willed and inactive. The search for new alternatives in business will be carried out continuously, but not chaotically, but according to certain concepts. There is no dogmatism in decision-making at all. So good luck to the ovals in their dialectical development and movement.

This text is an introductory piece. From the book Advertising text. Methodology of compilation and design author Berdyshev Sergey Nikolaevich

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From the book Illustrating Advertising author Nazaikin Alexander

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Definition

Oval
Ellipse

Comparison

The sum of the distances from the foci to any point on the curve is always the same and equal to the length of the major axis. This property is used by builders and designers to project figures on the ground. If the distance from the foci is the same, but more or less than the length of the major axis, then we are talking about an oval.

Findings site

Properties. For an ellipse, the sum of the distances from two foci lying on the major axis to a point on the curve is the same and equal to the length of the central axis.

geometric oval with one axis of symmetry

3. Oval in engineering graphics

In engineering graphics, an oval is usually understood as a figure with two axes of symmetry, built on a combination of four sections of curves of two radii. The segments of the arcs are chosen so that a smooth transition from one radius of curvature to another is ensured. A point moving along the perimeter of an oval is always on one of two fixed radii of curvature (unlike an ellipse, where the radius of curvature is constantly changing).

4. Oval in geometry

Just as in everyday speech, in geometry, the mathematical term "oval" occurs in the names of various geometric figures of a more or less oval shape, but without a precise definition of an oval as such. What these curves have in common is that they are usually closed, convex, smooth (with a tangent at any point) and have at least one axis of symmetry.

The term "ovaloid" is used in ovoid surfaces formed by the rotation of an oval curve around one of its axes of symmetry.

Other examples of ovals can be attributed.

The simplest mathematical terms can cause a real headache in a person who is far from the exact sciences. Such definitions as an oval and an ellipse are confused not only by schoolchildren, but also by quite adult people. Let's try to outline the differences between these concepts, using simple and accessible expressions, avoiding mathematical terms.

What is an oval and an ellipse

Oval- This is a closed elongated geometric figure with a regular shape and special properties. Inscribed in a circle, it has at least 4 extreme points, that is, vertices. If you divide the oval with a straight line along two opposite vertices, then the two segments obtained as a result of this action will be absolutely identical.
Ellipse is a closed flat curve, a special case of an oval that has 4 vertices at the extremum points. The central axis, drawn along two opposite extremum points, contains two focal points equidistant from the vertices. The sum of the distances from the foci to any point on the curve of the ellipse is a constant value, which is equal to the length of the central axis.
Ellipse

difference between oval and ellipse

Thus, the key difference between these concepts at the everyday level is captured through their definitions. There are many options for constructing an oval, the axes drawn from the points of their vertices can have a different ratio. If we are talking about an ellipse, then there are special conditions for its construction. There are 2 foci on the major axis, equidistant from the vertices.
The sum of the distances from the foci to any point on the curve is always the same and equal to the length of the major axis. This property is used by builders and designers to project figures on the ground. If the distance from the foci is the same, but more or less than the length of the major axis, then we are talking about an oval.

TheDifference.ru determined that the difference between an oval and an ellipse is as follows:

Volume. An oval is a broader concept, which includes an ellipse.
Properties. For an ellipse, the sum of the distances from two foci lying on the major axis to a point on the curve is the same and equal to the length of the central axis.

Oval- this is a closed box curve, having two axes of symmetry and consisting of two support circles of the same diameter, internally conjugated by arcs (Fig. 13.45). The oval is characterized by three parameters: length, width and radius of the oval. Sometimes only the length and width of the oval are specified, without determining its radii, then the problem of constructing an oval has a large number of solutions (see Fig. 13.45, a ... d).

They also use methods for constructing ovals based on two identical reference circles that are in contact (Fig. 13.46, a), intersect (Fig. 13.46, b) or do not intersect (Fig. 13.46, c). In this case, two parameters are actually set: the length of the oval and one of its radii. This problem has many solutions. It's obvious that R > OA has no upper bound. In particular R \u003d O 1 O 2(see fig. 13.46.a, and fig. 13.46.c), and the centers About 3 and About 4 are defined as the points of intersection of the base circles (see Fig. 13.46, b). According to the general point theory, conjugations are defined on a straight line connecting the centers of arcs of contiguous circles.

Constructing an oval with touching support circles(the problem has many solutions) ( rice. 3.44). From the centers of the support circles O and 0 1 with a radius equal, for example, to the distance between their centers, arcs of circles are drawn until they intersect at points O 2 and About 3 .

Figure 3.44

If from points O 2 and About 3 draw straight lines through the centers O and O 1, then at the intersection with the support circles we get conjugation points FROM, C1, D and D1. From points O 2 and About 3 as from centers with a radius R2 conduct conjugation arcs.

Constructing an oval with intersecting support circles(the problem also has many solutions) (Fig. 3.45). From the intersection points of the support circles From 2 and About 3 draw straight lines, for example, through the centers O and O 1 up to the intersection with the reference circles at the junction points C, C 1 D and D1, and the radii R2, equal to the diameter of the support circle - the conjugation arc.

Figure 3.45 Figure 3.46

Construction of an oval along two given axes AB and CD(Fig. 3.46). Below is one of many possible solutions. A segment is plotted on the vertical axis OE, half the major axis AB. From a point FROM how to draw an arc from the center with a radius CE up to the intersection with the segment AC at the point E 1. To the middle of the segment AE 1 restore the perpendicular and mark the points of its intersection with the axes of the oval O 1 and 0 2 . Build points O 3 and 0 4 , symmetrical to the points O 1 and 0 2 about the axes CD and AB. points O 1 and 0 3 will be the centers of the support circles of radius R1, equal to the segment About 1 A, and points O2 and 0 4 - centers of arcs of conjugation of radius R2, equal to the segment About 2 C. Straight lines connecting centers O 1 and 0 3 With O2 and 0 4 at the intersection with the oval, the junction points will be determined.

In AutoCAD, an oval is constructed using two reference circles of the same radius, which are:

1. have a point of contact;

2. intersect;

3. do not intersect.

Let's consider the first case. A segment OO 1 =2R is built, parallel to the X axis, at its ends (points O and O 1) the centers of two reference circles of radius R and the centers of two auxiliary circles of radius R 1 =2R are placed. From the intersection points of the auxiliary circles O 2 and O 3, arcs CD and C 1 D 1 are built, respectively. The auxiliary circles are removed, then, relative to the arcs CD and C 1 D 1, the inner parts of the support circles are cut off. In figure bb, the resulting oval is marked with a thick line.