# List of telescope parts and construction
## Hardware
### Accessories

* Finderscope
* Iron sight
* Reflector (reflex) sight
* Cheshire collimator: A simple tool to collimate a telescope

### Control

* Clock drive
* GoTo

### Mechanical construction

* Mirror support cell
* Serrurier truss
* Silvering

### Mounts

* Telescope mount - Types include:
** Altazimuth mount
** Equatorial mount
*** Equatorial platform
**** Poncet Platform
*** Fork mount
*** German equatorial mount
*** Springfield mount

### Optics

Mirrors and lenses are the critical light-bending components of a telescope.
* Objective: The first lens or curved mirror that collects and focuses the incoming light.
** Primary lens: The objective of a refracting telescope.
** Primary mirror: The objective of a reflecting telescope.
* Corrector plate: A full aperture negative lens placed before a primary mirror designed to correct the optical aberrations of the mirror.
** Schmidt corrector plate: An aspheric-shaped corrector plate used in the Schmidt telescope.
** Meniscus corrector: A meniscus-shaped corrector plate usually used in the Maksutov telescope.
* Focusing mask: A full aperture mask temporarily placed before the primary mirror to aid in focusing the telescope.
** Bahtinov mask
** Carey mask
** Hartmann mask
* Sub-aperture corrector: One or a series of corrective lens (sometimes combined with a corrective curved mirror) placed after (near the focus) a primary mirror designed to correct the optical aberrations of the mirror. These can be just a small version of the corrector plate, but since they are usually used in a Cassegrain configuration in front of the secondary mirror they require additional modification since the light passes through them twice.
* Secondary mirror
* Mirror § Instruments
* Curved mirror
* Honeycomb mirror
* Liquid mirror
* Parabolic reflector
Subsequent (sometimes optional) components realign, segment, or in some way modify the light of an incoming image:
* Field lens: A correcting lens placed just before the image plane of a telescope.
* Telecompressor or focal reducer: Optical element to decrease the telescope's focal length and magnification (usually by a fixed percentage) and widen the field of view, providing opposite effects of a Barlow lens.
* Star Diagonal: Used to change the angle of the light coming out of a telescope, for easier viewing.
* Herschel Wedge: Similar to a star diagonal with a wedge-shaped unsilvered prism reflector that reduces incoming light by up to 95% for solar viewing.
* Coma corrector a correcting lens used to reduce coma distortion in fast reflecting telescopes.
* Field flattener a correcting lens used to reduce field curvature in refracting telescopes for astrophotography.
* Barlow lens: Optical element to increase the telescope's focal length and magnification, narrow the field of view and reduce coma distortion, providing opposite effects of a telecompressor.
* Astronomical filter: Used to select specific colors (or light frequencies) for astrophotography.
* Filter wheel: One manner to easily insert filters into the optical train. Mostly used for photography.
* Focuser: Allows the user to adjust the focus by moving the eyepiece along the optical axis.
* Eyepiece: Performs the final focus correction before the light reaches the eye.
* Charge-coupled device (CCD): A light-sensitive integrated circuit digital sensor (commonly used in digital cameras) that turns light into an electrical charge used to collection image data.
Generally applicable to all items:
* Metallizing: A way of coating mirrors for high-efficiency light reflection.
* Optical coating: Thin layers applied to mirrors, filters, and lenses to avoid reflections, as well as absorb certain colors.

## Software and control interfaces

* Active optics
* Adaptive optics
* ASCOM
* EQMod
* INDI
* PLate OPtimizer
* Versatile Real-Time Executive

## Support equipment and buildings

* Observatory
   * Equatorial room