- published: 20 May 2013
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In optics, an aperture is a hole or an opening through which light travels. More specifically, the aperture of an optical system is the opening that determines the cone angle of a bundle of rays that come to a focus in the image plane. The aperture determines how collimated the admitted rays are, which is of great importance for the appearance at the image plane. If an aperture is narrow, then highly collimated rays are admitted, resulting in a sharp focus at the image plane. If an aperture is wide, then uncollimated rays are admitted, resulting in a sharp focus only for rays with a certain focal length. This means that a wide aperture results in an image that is sharp around what the lens is focusing on and blurred otherwise. The aperture also determines how many of the incoming rays are actually admitted and thus how much light reaches the image plane (the narrower the aperture, the darker the image for a given exposure time).
An optical system typically has many openings, or structures that limit the ray bundles (ray bundles are also known as pencils of light). These structures may be the edge of a lens or mirror, or a ring or other fixture that holds an optical element in place, or may be a special element such as a diaphragm placed in the optical path to limit the light admitted by the system. In general, these structures are called stops, and the aperture stop is the stop that determines the ray cone angle, or equivalently the brightness, at an image point.
"Choose the right" is a saying or motto among members of The Church of Jesus Christ of Latter-day Saints (LDS Church) that is taught to children and used by members of the church as a reminder to act righteously. The phrase is taken from an LDS hymn which has that title.
The letters CTR, a reference to this phrase, are incorporated into a shield logo designed by Helen Alldredge, a Primary General Board member in the 1960s. In 1970, a church committee headed by Naomi W. Randall recommended that the shield be incorporated into official church material. Since then, both the phrase and symbol have been used in religious educational materials for LDS youth of Primary age. The symbol is also used in LDS culture by members of all ages, both as a reminder of the motto, as well as an indicator of religious affiliation. The CTR initials, displayed on the shield and in other forms, can be seen mainly on CTR rings as well as other types of jewelry, tee shirts, bookmarks and stationery.
According to the US Patent and Trademark Office, the LDS Church's stylized "CTR" abbreviation and shield with the CTR symbol are trademarked for use on finger ring jewelry by Intellectual Reserve. The phrase "Choose the Right," however, is not trademarked in the United States and may be used by anyone for commercial purposes.[citation needed]
Happiness is somewhere i have been before-
A blurry photograph that i have since ignored.
I'll carefully adjust the aperture once more,
Until i set the record straight.
I'll brush aside the dim, make room for the bright.
I'll be an editor, no, a curator of light.
I'll let my better angels always set me right,
Until i even out the score.
Until i even out the score.
God, it has been quite a year-
I've lived a little bit and i've died a little more.
I know that i've asked it before,
But please let the scale tip here in my favor.
What was once the sweetest melody i've heard
Is now a memory reduced to little words.
I'll tune the orchestra and play the overture,
Until i pinpoint every note.
Give me the heart of an archeologist,
That i may dig until i prove that i exist.
A subterranean cathedral in my midst,
Where echos come to rest.
Where echos come to rest.
Is this where echos come to rest?
God, it has been quite a year-
I've lived a little bit and i've died a little more.
I know that i've asked it before,
But please let the scale tip here in my favor.
Until i set the record straight,
Until i set the record straight,